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Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Corporate income tax rate	21.00%			35.00%
Effect Of Tax Cuts and Jobs Act [Abstract]
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)			$ 6,400,000	$ 101,600,000
Revaluation of deferred tax assets and liabilities			2,000,000.0	3,900,000
Provisional impact of U.S. Tax Reform			(4,353,000)	97,700,000
Tax Cuts And Jobs Act Of 2017 Accounting Completion Date	Dec. 31, 2018
Tax Cuts and Jobs Act, Transition Tax for Accumulated Foreign Earnings Liability	$ 51,900,000
Tax Cuts and Jobs Act, transition tax for accumulated foreign earnings liability noncurrent	45,500,000
Foreign earnings repatriated	25,000,000.0	$ 52,100,000
Cumulative undistributed earnings of foreign subsidiaries	333,600,000
Unrecognized deferred tax liability	3,700,000
Impact of cash repatriation			21,612,000
Revaluation of deferred tax assets and liabilities			2,000,000.0	3,900,000
Provisional impact of U.S. Tax Reform			(4,353,000)	97,700,000
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)			6,400,000	$ 101,600,000
Net change in total deferred tax asset valuation allowance	$ 3,000,000.0	2,300,000	(2,100,000)
Tax credit carryforward expiration year	2026
Income tax incentives	$ 7,400,000	$ 5,000,000.0	$ 7,900,000
Net impact of tax incentives, per diluted share	$ 0.20	$ 0.13	$ 0.17
Unrecognized tax benefits including interest and penalties	$ 600,000
Additions related to prior year tax positions		$ 200,000
Decreases related to prior year tax positions	14,000.0		$ 532,000
Interest on unrecognized tax	100,000
Penalty on unrecognized tax	17,000.0
Interest and penalties included in income tax expense	$ 0	$ 0	100,000
Thailand [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Income tax holidays expiration date	2028
Earliest Tax Year [Member] \| Malaysia [Member}
Effect Of Tax Cuts and Jobs Act [Abstract]
Income tax holidays expiration date	2021
Latest Tax Year [Member] \| Malaysia [Member}
Effect Of Tax Cuts and Jobs Act [Abstract]
Income tax holidays expiration date	2026
Foreign [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Impact of cash repatriation			30,800,000
Operating loss carryforwards	$ 38,900,000
Foreign operating loss with indefinite carry forward period	$ 13,000,000.0
Foreign [Member] \| Latest Tax Year [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Operating loss carryforwards expiration Year	2030
U.S. Federal [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)			3,200,000
Revaluation of deferred tax assets and liabilities			9,200,000
Provisional impact of U.S. Tax Reform			4,400,000
Revaluation of deferred tax assets and liabilities			9,200,000
Provisional impact of U.S. Tax Reform			4,400,000
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)			$ 3,200,000
Operating loss carryforwards	$ 8,500,000
U.S. Federal [Member] \| Earliest Tax Year [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Tax credit carryforward expiration year	2027
U.S. Federal [Member] \| Latest Tax Year [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Tax credit carryforward expiration year	2036
State and local [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Operating loss carryforwards	$ 44,500,000
Tax credit carryforward	$ 1,800,000
State and local [Member] \| Earliest Tax Year [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Operating loss carryforwards expiration Year	2021
State and local [Member] \| Latest Tax Year [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Operating loss carryforwards expiration Year	2031
Research Tax Credit Carryforward [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Tax credit carryforward	$ 1,600,000
Research Tax Credit Carryforward [Member] \| Earliest Tax Year [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Tax credit carryforward expiration year	2038
Research Tax Credit Carryforward [Member] \| Latest Tax Year [Member]
Effect Of Tax Cuts and Jobs Act [Abstract]
Tax credit carryforward expiration year	2040