Commitments and Contingencies Lease Commitments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, Rent Expense, Net	$ 2,752	$ 1,402	$ 1,500	$ 1,500	$ 1,661	$ 1,675
Operating Leases, Rent Expense, Minimum Rentals	2,752	1,402	1,500	1,500	1,685	1,820
Operating Leases, Future Minimum Payments Due						10,659
Operating Leases, Rent Expense, Sublease Rentals						169
Operating Leases, Income Statement, Lease Revenue	0		0	0	24	145
Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals						$ 10,490