Derivative Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Cash Flow Hedge Loss at Settlement Date	$ 3,257
Cash Flow Loss Reclassified to Interest Expense at Settlement Date	1,990
OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetofTaxBeforeSettlement	886
InterestRateSwapLossReclassifiedToInterestExpense	$ (1,080)

Net of tax amount, before reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss) prior to the settlement date

No definition available.

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