Goodwill and Other Intangibles Estimated Intangible Asset Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Finite-Lived Intangible Assets [Line Items]
2017	$ 5,470
2018	5,365
2019	5,112
2020	4,985
2021	4,737
Later	24,902
Finite-Lived Intangible Assets, Net	50,571
Customer Relationships Intangible [Member]
Finite-Lived Intangible Assets [Line Items]
2017	3,340
2018	3,340
2019	3,340
2020	3,340
2021	3,340
Later	23,506
Finite-Lived Intangible Assets, Net	40,206	$ 17,061	$ 18,746
Production and Supply Contract Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
2017	1,282
2018	1,405
2019	1,405
2020	1,397
2021	1,397
Later	1,396
Finite-Lived Intangible Assets, Net	8,282	9,107	10,141
Internally Developed Software Intangible [Member]
Finite-Lived Intangible Assets [Line Items]
2017	848
2018	620
2019	367
2020	248
2021	0
Later	0
Finite-Lived Intangible Assets, Net	$ 2,083	$ 2,929	$ 3,044