Reclassification of AOCI to Earnings (Details) (USD $)	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Reclassification of Aoci To Earnings [Abstract]
Reclassify net losses on interest rate contracts from AOCI to earnings over the next twelve months	$ 14,200,000
Loss reclassified from AOCI into income (effective portion)	$ 16,691,000	$ 19,178,000	$ 23,559,000

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624177-113959

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration