Long-Term Debt Other Senior Notes and Senior Subordinated Notes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,203,035	$ 1,116,562
Payments of debt issuance costs	8,820	3,722	36,273
12 3/4% Senior Subordinated Notes Due 2012 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			12.75%
9 5/8% Senior Notes Due 2011 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			9.625%
7 3/4% Senior Notes Due 2013 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			7.75%
8.5% Senior Notes, Due 2012 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			8.50%
Subordinated Debt [Member]
Debt Instrument [Line Items]
Amortization of financing costs			5,591
Amortization of debt discount (premium)			5,563
Long-term debt, gross	621,189	617,756
Subordinated Debt [Member] | 8.5% Senior Notes, Due 2012 [Member]
Debt Instrument [Line Items]
Debt instrument, repurchase amount		23,635	120,365
Debt instrument, interest rate	8.50%
Amortization of debt discount (premium)		282
Long-term debt, gross	6,000	6,000
Payments of debt issuance costs		$ 650
Subordinated Debt [Member] | 11% Senior Notes, Due 2012 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			11.00%
Subordinated Debt [Member] | 8% Senior Notes Due 2012 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			8.00%