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USD ($)
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12/31/2010
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12/31/2009
USD ($)
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12/31/2010
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12/31/2009
USD ($)
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/IsTotalLabel>false212Derivative Financial Instruments (Notional Amount of Interest Rate Swap Agreements Designated as Fair Value and Cash Flow Hedges) (Details) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue
