Income Taxes Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Operating Loss Carryforwards [Line Items]
Valuation allowance, deferred tax asset, increase (decrease), amount	$ 5,800,000	$ 112,700,000
Change in U.S. valuation allowance		67,800,000
Deferred tax assets, valuation allowance	$ 64,477,000	$ 58,658,000
Statutory tax rate, percent	21.00%	21.00%	31.60%
Deferred tax liabilities, unremitted foreign earnings	$ 0
Unrecognized tax benefits	19,367,000	$ 18,877,000	$ 8,680,000	$ 7,390,000
Unrecognized tax benefits that would impact effective tax rate	17,400,000
Amount of unrecorded benefit	5,800,000
Income tax penalties and interest accrued	500,000	500,000
Net foreign taxable income reported on prior year federal income tax return	40,100,000
Income tax expense (benefit)	$ 38,526,000	$ (39,460,000)	$ 9,132,000
Macedonia
Operating Loss Carryforwards [Line Items]
Statutory tax rate, percent	0.00%	10.00%	10.00%
THAILAND
Operating Loss Carryforwards [Line Items]
Statutory tax rate, percent	0.00%	20.00%
Valuation Allowance for Deferred Tax Assets
Operating Loss Carryforwards [Line Items]
Valuation allowances and reserves	$ 64,477,000	$ 58,658,000	$ 171,401,000	$ 163,898,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Valuation allowance, deferred tax asset, increase (decrease), amount		44,900,000
Operating loss carryforwards	114,400,000
Operating loss carryforwards subject to expiration within one year	0
Deferred tax assets, valuation allowance	41,000,000.0
Foreign Tax Authority | Changes in Temporary Differences and Net Operating Utilizations of Deferred Tax Assets
Operating Loss Carryforwards [Line Items]
Valuation allowance, deferred tax asset, increase (decrease), amount		(35,500,000)
Foreign Tax Authority | Release of Valuation Allowance of Deferred Tax Assets
Operating Loss Carryforwards [Line Items]
Valuation allowance, deferred tax asset, increase (decrease), amount		(5,500,000)
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	82,400,000
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	75,300,000
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration	7,100,000
Deferred tax assets, valuation allowance	23,500,000
Domestic Tax Authority | Release of Valuation Allowance of Deferred Tax Assets
Operating Loss Carryforwards [Line Items]
Valuation allowance, deferred tax asset, increase (decrease), amount		(44,200,000)
Domestic Tax Authority | Operating Loss Carryforwards of Deferred Tax Assets
Operating Loss Carryforwards [Line Items]
Valuation allowance, deferred tax asset, increase (decrease), amount		$ (26,900,000)
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	545,000,000.0
Operating loss carryforwards subject to expiration within one year	$ 1,600,000
Operating loss carryforwards, expiration period	1 year
Investment Tax Credit Carryforward [Member] | Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Fiscal Year of Expiration	Dec. 31, 2028
Texas franchise tax credits
Operating Loss Carryforwards [Line Items]
Fiscal Year of Expiration	Dec. 31, 2026
Minimum | U.S. research credits
Operating Loss Carryforwards [Line Items]
Fiscal Year of Expiration	Dec. 31, 2022
Maximum [Member] | U.S. research credits
Operating Loss Carryforwards [Line Items]
Fiscal Year of Expiration	Dec. 31, 2025