Goodwill and Intangibles Asset Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended						6 Months Ended
	Sep. 30, 2016	Jun. 30, 2016		Sep. 30, 2015	Jun. 30, 2015		Sep. 30, 2016	Mar. 31, 2016		Mar. 31, 2015
Goodwill and Intangible Assets [Line Items]
Goodwill	$ 16,463	$ 16,463	[1]	$ 2,794	$ 2,794	[1]	$ 16,463	$ 16,463	[1]	$ 2,794	[1]
Gross balance										69,889
Amortizable Intangibles, Accumulated amortization										(37,998)
Goodwill, Acquired During Period								13,669
Finite-lived Intangible Assets [Roll Forward]
Net balance	65,895	67,034		30,994	31,891		67,034	30,098
Additions								38,499
Amortization expense	(1,030)	(1,139)		(896)	(897)			(1,563)
Net balance	64,865	65,895		30,098	30,994		64,865	67,034
North America
Goodwill and Intangible Assets [Line Items]
Goodwill	2,794						2,794
Other Regions
Goodwill and Intangible Assets [Line Items]
Goodwill	13,669						$ 13,669
Customer Relationships Intangible
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years							12 years 6 months
Amortizable Intangibles, Gross carrying amount										33,700
Amortizable Intangibles, Accumulated amortization										(16,639)
Finite-lived Intangible Assets [Roll Forward]
Net balance	39,370	40,206		16,640	17,061		$ 40,206	16,219
Additions								24,830
Amortization expense	(834)	(836)		(421)	(421)			(843)
Net balance	38,536	39,370		16,219	16,640		$ 38,536	40,206
Production and Supply Contract Intangibles
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years							4 years 3 months
Amortizable Intangibles, Gross carrying amount										14,893
Amortizable Intangibles, Accumulated amortization										(5,786)
Finite-lived Intangible Assets [Roll Forward]
Net balance	8,172	8,282		8,837	9,107		$ 8,282	8,565
Additions								0
Amortization expense	(8)	(110)		(272)	(270)			(283)
Net balance	8,164	8,172		8,565	8,837		$ 8,164	8,282
Internally Developed Software Intangible
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years							0 years
Amortizable Intangibles, Gross carrying amount										18,502
Amortizable Intangibles, Accumulated amortization										$ (15,573)
Finite-lived Intangible Assets [Roll Forward]
Net balance	1,890	2,083		2,723	2,929		$ 2,083	2,520
Additions								0
Amortization expense	(188)	(193)		(203)	(206)			(437)
Net balance	$ 1,702	$ 1,890		$ 2,520	$ 2,723		$ 1,702	$ 2,083

[1] Goodwill of $2,794 relates to the North America segment and $13,669 relates to the Other Regions segment.