Debt (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Interest expense
Contractual interest expense	$ 38,716	$ 37,366	$ 37,193
Amortization of debt issuance costs	1,467us-gaap_AmortizationOfFinancingCosts	1,704us-gaap_AmortizationOfFinancingCosts	1,704us-gaap_AmortizationOfFinancingCosts
Amortization of debt (premium) discount	(407)	105	(183)
Imputed interest on acquisition related obligations	754	1,787	2,617
Capital Leases, Income Statement, Interest Expense	171	0	0
Total interest expense	$ 40,701us-gaap_InterestExpense	$ 40,962us-gaap_InterestExpense	$ 41,331us-gaap_InterestExpense

Amount of noncash expense included in interest expense for acquisition related obligations of the entity.

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense.

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The financing charge for leasing arrangements meeting the criteria for capitalization.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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