Goodwill and Other Intangibles Goodwill and Intangible Asset Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Goodwill and Intangible Assets [Line Items]
Unamortizable Goodwill	$ 2,794	$ 2,794	$ 2,794
Gross balance			61,305
Amortizable Intangibles, Accumulated amortization			(29,834)
Net balance	34,725	31,471
Additions	698	7,886
Amortizable Intangibles, Amortization expense	(3,532)	(4,632)	(5,370)
Amortizable Intangibles, Net	29,097
Net balance	31,891	34,725	31,471
North America [Member]
Goodwill and Intangible Assets [Line Items]
Unamortizable Goodwill	$ 2,794	2,794	2,794
Customer Relationships Intangible [Member]
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years as of March 31, 2015	10 years
Amortizable Intangibles, Gross carrying amount			33,700
Amortizable Intangibles, Accumulated amortization			(13,269)
Amortizable Intangibles, Net	$ 18,746	20,431
Additions	0	0
Amortizable Intangibles, Amortization expense	(1,685)	(1,685)
Amortizable Intangibles, Net	$ 17,061	18,746	20,431
Production and Supply Contract Intangibles [Member]
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years as of March 31, 2015	5 years 9 months
Amortizable Intangibles, Gross carrying amount			7,893
Amortizable Intangibles, Accumulated amortization			(3,657)
Amortizable Intangibles, Net	$ 10,141	4,236
Additions	0	7,000
Amortizable Intangibles, Amortization expense	(1,034)	(1,095)
Amortizable Intangibles, Net	$ 9,107	10,141	4,236
Internally Developed Software Intangible [Member]
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years as of March 31, 2015	0 years
Amortizable Intangibles, Gross carrying amount			16,918
Amortizable Intangibles, Accumulated amortization			(12,908)
Amortizable Intangibles, Net	$ 3,044	4,010
Additions	698	886
Amortizable Intangibles, Amortization expense	(813)	(1,852)
Amortizable Intangibles, Net	$ 2,929	$ 3,044	$ 4,010