Reclassification of AOCI to Earnings (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jun. 30, 2012
Derivative instruments, gain (loss) recognized in AOCI, effective portion:
Reclassify net losses on interest rate contracts from AOCI to earnings over the next twelve months	$ 18.4

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