Accumulated Other Comprehensive Income (Loss) (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Comprehensive Income (Loss) (Textual) [Abstract]
Estimated after-tax gain on derivatives to be reclassified from AOCI to earnings within the next 12 months	$ 3

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

No definition available.

Name:	us-gaap_DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration