Debt (Details) - USD ($)	3 Months Ended				9 Months Ended
	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Jan. 09, 2017	May 02, 2016
Debt
Document Period End Date					Dec. 31, 2016
Debt, Long-term and Short-term, Combined Amount [Abstract]
Total debt	$ 386,226,000	$ 387,833,000			$ 386,226,000
Revolving line of credit	33,881,000	33,881,000			33,881,000
Current maturities	0	(2,000,000)			0
Total long-term debt	386,226,000	385,833,000			386,226,000
Amortization of financing and debt discount		(1,000,000)			(700,000)
Interest expense
Contractual interest expense	9,693,000		$ 9,761,000		29,091,000	$ 29,332,000
Capitalized interest	(48,000)		(163,000)		(151,000)	(439,000)
Amortization of debt issuance costs	348,000		348,000		1,044,000	1,044,000
Amortization of debt (premium) discount	(204,000)		(188,000)		(603,000)	(554,000)
Imputed interest on acquisition-related obligations	39,000		52,000		120,000	159,000
Interest expense on capital lease	90,000		42,000		250,000	134,000
Total interest expense	9,918,000		$ 9,852,000		29,751,000	29,676,000
Line of Credit Facility [Abstract]
Additional Borrowings					0
Repayments					0	$ 5,500,000
10.5% Senior Notes, net [Member]
Debt, Long-term and Short-term, Combined Amount [Abstract]
Total debt	352,345,000	353,952,000			$ 352,345,000
Amortization of financing and debt discount	$ (655,000)			$ (1,047,000)
Line of Credit Facility [Abstract]
Rate	10.50%				10.50%
Long-term Debt, Unclassified [Abstract]
Repayments of debt					$ 2,000,000
Long-term debt outstanding	$ 353,000,000	354,999,000			353,000,000
Interest payable	6,178,000	15,500,000			6,178,000
Revolving Credit Facility [Member]
Line of Credit Facility [Abstract]
Current borrowing capacity								$ 65,000,000
Remaining borrowing capacity	31,100,000				31,100,000
Domestic Line of Credit [Member]
Debt, Long-term and Short-term, Combined Amount [Abstract]
Revolving line of credit	$ 19,881,000	19,881,000			19,881,000
Line of Credit Facility [Abstract]
Additional Borrowings					0
Repayments					$ 0
Domestic Line of Credit [Member] | Base Rate [Member]
Line of Credit Facility [Abstract]
Rate	5.00%				5.00%
Foreign Line of Credit [Member]
Line of Credit Facility [Abstract]
Additional Borrowings					$ 0
Foreign Line of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Abstract]
Basis spread on variable rate					2.50%
Foreign Line of Credit [Member] | Letter of Credit One [Member]
Debt, Long-term and Short-term, Combined Amount [Abstract]
Revolving line of credit	$ 12,000,000	12,000,000			$ 12,000,000
Foreign Line of Credit [Member] | Letter of Credit One [Member] | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Abstract]
Rate	3.50%				3.50%
Foreign Line of Credit [Member] | Letter of Credit Two [Member]
Debt, Long-term and Short-term, Combined Amount [Abstract]
Revolving line of credit	$ 2,000,000	$ 2,000,000			$ 2,000,000
Foreign Line of Credit [Member] | Letter of Credit Two [Member] | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Abstract]
Rate	3.375%				3.375%
US Facility [Member] | Base Rate [Member]
Line of Credit Facility [Abstract]
Basis spread on variable rate					1.50%
Subsequent Event [Member] | Foreign Line of Credit [Member] | Letter of Credit Two [Member] | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Abstract]
Rate							3.625%