FAIR VALUE MEASUREMENTS - Fair Value, Assets and Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2020 |
Jun. 30, 2019 |
Jun. 30, 2020 |
Jun. 30, 2019 |
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| Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation [Roll Forward] | Ìý | Ìý | Ìý | Ìý |
| Beginning balance | $ 19.6 | $ 106.7 | $ 45.8 | $ 91.4 |
| Included in earnings | 40.0 | 74.3 | 13.8 | 89.6 |
| Settlements | (24.3) | (62.9) | (24.3) | (62.9) |
| Ending balance | 35.3 | 118.1 | 35.3 | 118.1 |
| Total gains for the period included in earnings attributable to the change in unrealized gains on assets still held at the reporting date | 33.6 | 73.0 | 13.6 | 88.3 |
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] | Ìý | Ìý | Ìý | Ìý |
| Beginning balance | 0.0 | (9.8) | (1.1) | 0.0 |
| Included in earnings | 0.0 | 4.5 | (0.6) | (5.3) |
| Settlements | 0.0 | 5.3 | 1.7 | 5.3 |
| Ending balance | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0 |
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- Definition Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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