Deferred Income (New Markets Tax Credit Transaction) (Details) (USD $)			12 Months Ended				0 Months Ended		12 Months Ended
	Mar. 31, 2013	Sep. 30, 2012	Sep. 30, 2012 New Markets Tax Credit Transaction	Mar. 31, 2013 New Markets Tax Credit Transaction	Mar. 31, 2013 Primary beneficiary NMTC program special-purpose entity New Markets Tax Credit Transaction	Sep. 30, 2012 Primary beneficiary NMTC program special-purpose entity New Markets Tax Credit Transaction	Sep. 11, 2012 Primary beneficiary Investor NMTC program special-purpose entity New Markets Tax Credit Transaction	Feb. 03, 2012 Primary beneficiary Investor NMTC program special-purpose entity New Markets Tax Credit Transaction	Sep. 30, 2012 Primary beneficiary Investor NMTC program special-purpose entity New Markets Tax Credit Transaction	Mar. 31, 2013 Primary beneficiary Newark Joint Venture Subsidiaries New Markets Tax Credit Transaction	Sep. 30, 2012 Primary beneficiary Newark Joint Venture Subsidiaries New Markets Tax Credit Transaction
Deferred Income (New Markets Tax Credit Transaction)
Maximum percentage of qualified investment permitted in NMTC to claim credits against Federal income tax				39.00%
Amount contributed to effect financing transaction							$ 11,200,000	$ 16,400,000
Period over which tax credits is receivable									7 years
Deferred income	25,848,000	25,848,000			25,848,000	25,848,000
Recapture period			7 years
Deferred costs, net	$ 12,207,000	$ 12,337,000								$ 9,900,000	$ 10,200,000