DEBT AND CREDIT FACILITIES - Schedule Of Long-Term Debt (Details) - USD ($) $ in Millions |
Jun. 30, 2020 |
Jun. 19, 2020 |
Apr. 24, 2020 |
Apr. 17, 2020 |
Mar. 16, 2020 |
Mar. 13, 2020 |
Dec. 31, 2019 |
Debt Instrument [Line Items] |
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Long-term Debt, Gross |
$ 4,640.7
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LONG-TERM DEBT |
4,451.6
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$ 2,113.8
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9.875% 2025 Senior Secured Notes [Member] |
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Debt Instrument [Line Items] |
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Long-term Debt, Gross |
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$ 555.2
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$ 400.0
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6.75% 2026 Senior Secured Notes [Member] |
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Debt Instrument [Line Items] |
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Long-term Debt, Gross |
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$ 120.0
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$ 725.0
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6.375% 2025 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Long-term Debt, Gross |
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$ 231.8
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7.00% 2027 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Long-term Debt, Gross |
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$ 335.4
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Credit Facility |
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Debt Instrument [Line Items] |
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Long-term Line of Credit |
$ 550.0
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 4.875% 2024 Senior Secured Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
5.00%
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5.00%
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Long-term Debt, Gross |
$ 394.5
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$ 400.0
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Unamortized Debt Issuance Expense |
(4.0)
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(4.6)
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Debt Instrument, Unamortized Discount |
(1.6)
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(1.8)
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Long-term Debt |
$ 388.9
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$ 393.6
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 9.875% 2025 Senior Secured Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
10.57%
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Long-term Debt, Gross |
$ 955.2
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Unamortized Debt Issuance Expense |
(8.7)
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Debt Instrument, Unamortized Discount |
(26.7)
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Long-term Debt |
$ 919.8
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 6.75% 2026 Senior Secured Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
6.99%
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Long-term Debt, Gross |
$ 845.0
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Unamortized Debt Issuance Expense |
(22.6)
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Debt Instrument, Unamortized Discount |
(9.4)
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Long-term Debt |
$ 813.0
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 6.375% 2025 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
8.11%
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Long-term Debt, Gross |
$ 64.3
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Unamortized Debt Issuance Expense |
(0.2)
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Debt Instrument, Unamortized Discount |
(4.8)
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Long-term Debt |
$ 59.3
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 1.50% 2025 Convertible Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
6.26%
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6.26%
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Long-term Debt, Gross |
$ 296.3
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$ 316.3
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Unamortized Debt Issuance Expense |
(3.9)
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(4.6)
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Debt Instrument, Unamortized Discount |
(55.6)
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(65.0)
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Long-term Debt |
$ 236.8
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$ 246.7
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 5.75% 2025 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
6.01%
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6.01%
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Long-term Debt, Gross |
$ 396.2
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$ 473.3
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Unamortized Debt Issuance Expense |
(2.8)
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(3.6)
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Debt Instrument, Unamortized Discount |
(4.3)
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(5.5)
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Long-term Debt |
$ 389.1
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$ 464.2
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 7.00% 2027 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
9.24%
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Long-term Debt, Gross |
$ 88.0
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Unamortized Debt Issuance Expense |
(0.3)
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Debt Instrument, Unamortized Discount |
(9.8)
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Long-term Debt |
$ 77.9
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 5.875% 2027 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
6.49%
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6.49%
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Long-term Debt, Gross |
$ 555.5
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$ 750.0
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Unamortized Debt Issuance Expense |
(4.5)
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(6.3)
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Debt Instrument, Unamortized Discount |
(19.0)
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(27.3)
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Long-term Debt |
$ 532.0
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$ 716.4
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ÐÇ¿Õ´«Ã½ Inc. [Member] | 6.25% 2040 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
6.34%
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6.34%
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Long-term Debt, Gross |
$ 262.7
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$ 298.4
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Unamortized Debt Issuance Expense |
(1.9)
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(2.2)
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Debt Instrument, Unamortized Discount |
(2.8)
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(3.3)
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Long-term Debt |
$ 258.0
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292.9
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ÐÇ¿Õ´«Ã½ Inc. [Member] | Credit Facility |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
2.79%
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Long-term Debt, Gross |
$ 2,000.0
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450.0
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Long-term Line of Credit |
$ 550.0
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$ 0.0
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AK Steel Holding Corporation [Member] | 7.625% 2021 Senior Notes [Member] |
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Debt Instrument [Line Items] |
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Debt Instrument, Interest Rate, Effective Percentage |
7.33%
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Long-term Debt, Gross |
$ 33.5
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Unamortized Debt Issuance Expense |
0.0
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Debt Instrument, Unamortized Premium |
0.1
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Long-term Debt |
$ 33.6
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AK Steel Holding Corporation [Member] | 7.50% 2023 AK Senior Notes [Member] |
Ìý
|
Ìý
|
Ìý
|
Ìý
|
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|
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|
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Debt Instrument [Line Items] |
Ìý
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Debt Instrument, Interest Rate, Effective Percentage |
6.17%
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Long-term Debt, Gross |
$ 12.8
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Unamortized Debt Issuance Expense |
0.0
|
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument, Unamortized Premium |
0.5
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Ìý
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Ìý
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Ìý
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Ìý
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Long-term Debt |
$ 13.3
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Ìý
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AK Steel Holding Corporation [Member] | 6.375% 2025 AK Senior Notes [Member] |
Ìý
|
Ìý
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Ìý
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Ìý
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|
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Debt Instrument [Line Items] |
Ìý
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Ìý
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Debt Instrument, Interest Rate, Effective Percentage |
8.11%
|
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Long-term Debt, Gross |
$ 38.4
|
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Unamortized Debt Issuance Expense |
0.0
|
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument, Unamortized Discount |
(2.9)
|
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Long-term Debt |
$ 35.5
|
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
AK Steel Holding Corporation [Member] | 7.00% 2027 AK Senior Notes [Member] |
Ìý
|
Ìý
|
Ìý
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Ìý
|
Ìý
|
Ìý
|
Ìý
|
Debt Instrument [Line Items] |
Ìý
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Ìý
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Ìý
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Ìý
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Debt Instrument, Interest Rate, Effective Percentage |
9.24%
|
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Long-term Debt, Gross |
$ 56.3
|
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Unamortized Debt Issuance Expense |
0.0
|
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|
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
|
Debt Instrument, Unamortized Discount |
(6.2)
|
Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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Long-term Debt |
50.1
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Ìý
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Ìý
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Ìý
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Ìý
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Ìý
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AK Steel Holding Corporation [Member] | Industrial Revenue Bonds [Member] |
Ìý
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Ìý
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Debt Instrument [Line Items] |
Ìý
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Ìý
|
Long-term Debt, Gross |
92.0
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Unamortized Debt Issuance Expense |
0.0
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Debt Instrument, Unamortized Premium |
2.3
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Long-term Debt |
$ 94.3
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|
Ìý
|