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Fair Value of Financial Instruments (Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation) (Details) (USD $)
In Millions |
3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2011
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Jun. 30, 2010
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Jun. 30, 2011
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Jun. 30, 2010
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| Fair Value of Financial Instruments | Ìý | Ìý | Ìý | Ìý |
| Beginning balance - January 1 | $ 68.1 | $ 171.0 | $ 45.6 | $ 63.2 |
| Total gains (losses) | Ìý | Ìý | Ìý | Ìý |
| Included in earnings | 46.5 | 437.7 | 91.1 | 799.8 |
| Included in other comprehensive income | Ìý | Ìý | Ìý | Ìý |
| Settlements | (30.6) | (369.8) | (52.7) | (624.1) |
| Transfers out of Level 3 | (20.0) | Ìý | (20.0) | Ìý |
| Ending balance - March 31 | 64.0 | 238.9 | 64.0 | 238.9 |
| Total gains (losses) for the period included in earnings attributable to the change in unrealized gains or losses on assets and liabilities still held at the reporting date | $ 46.5 | $ 400.9 | $ 91.1 | $ 639.8 |
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- Definition
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Abstract]
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- Definition
Fair Value Measurement with Unobservable Inputs Reconciliation Recurring Basis Asset and Liabilities, Change in Unrealized Gains Losses Included in Earnings on Instruments Still Held
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- Definition
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset and Liabilities, Included in Earnings
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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset and Liabilities, Included in Other Comprehensive Income
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- Definition
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset and Liabilities, Settlements
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- Definition
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level Three
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- Definition
This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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