Income Taxes - NOL and Tax Credits (Details) $ in Thousands	12 Months Ended
	Mar. 31, 2016 USD ($)
U.S. research credits
Tax credit carryforwards
Tax credits	$ 1,425
Fiscal Year of Expiration	2023
Texas franchise tax credits
Tax credit carryforwards
Tax credits	$ 3,242
Fiscal Year of Expiration	2026
Foreign Tax Authority [Member]
Tax credit carryforwards
Operating Loss Carryforwards	$ 59,600
Tax credits	$ 5,173
Fiscal Year of Expiration	2017
Macedonia
Tax credit carryforwards
Income Tax Expense (Benefit)	$ 0
Domestic Tax Authority [Member]
Tax credit carryforwards
Operating Loss Carryforwards	417,900
State and Local Jurisdiction [Member]
Tax credit carryforwards
Operating Loss Carryforwards	497,700
Operating Loss Carryforwards Subject to Expiration within One Year	$ 3,000
Operating Loss Carryforwards, Expiration Period	1 year