Fair Value Of Financial Instruments (Fair Value, Assets And Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation) (Details) (USD $) In Millions |
3 Months Ended | 9 Months Ended | ||
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Sep. 30, 2011 |
Sep. 30, 2010 |
Sep. 30, 2011 |
Sep. 30, 2010 |
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| Fair Value Of Financial Instruments [Abstract] | ||||
| Beginning balance | $ 64.0 | $ 238.9 | $ 45.6 | $ 63.2 |
| Included in earnings | 53.8 | 25.1 | 144.9 | 824.9 |
| Settlements | (50.0) | (56.4) | (102.7) | (680.5) |
| Transfers out of Level 3 | 161.8 | 20.0 | 161.8 | |
| Ending balance - September 30 | 67.8 | 45.8 | 67.8 | 45.8 |
| Total gains for the period included in earnings attributable to the change in unrealized gains on assets still held at the reporting date | $ 53.8 | $ 25.1 | $ 144.9 | $ 93.4 |
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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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- 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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