Debt (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Sep. 30, 2013		Mar. 31, 2013
Total long-term debt
DIP Credit Agreement	$ 284,625		$ 0
Other, including capital lease obligations and other loans at interest rates generally ranging up to 6.2% due in installments through 2018	20,272		20,457
Total debt	304,897		751,207
Fair value adjustments on hedged debt	0		2,788
Total	304,897		753,995
Less-current maturities	(286,349)		(60,131)
Long term debt	18,548		693,864
Stated interest rate	6.20%
Basis spread on variable rate	1.00%
8 5/8% Senior Secured Notes due 2018 [Member]
Total long-term debt
8 5/8% Senior Secured Notes due 2018	0	[1]	675,000	[1]
Stated percentage	8.625%
Floating Rate Convertible Senior Subordinated Notes due September 2013 [Member]
Total long-term debt
Floating Rate Convertible Senior Subordinated Notes due September 2013	$ 0	[1]	$ 55,750	[1]

[1] (a) The pre-petition debt of the Debtor was reclassified to liabilities subject to compromise.