Income Taxes Income Tax Expense Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%	35.00%
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate	$ (21,570)	$ 16,440	$ 19,390
Income Tax Reconciliation, State and Local Income Taxes	(2,850)	970	2,730
Income Tax Reconciliation, Foreign Income Tax Rate Differential	(1,500)	(870)	490
Income Tax Reconciliation, Tax Contingencies	(920)	(920)	(560)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount	13,430	0	0
Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount	0	(570)	(940)
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	(2,130)	(1,160)	(1,740)
Income Tax Reconciliation, Change in Deferred Tax Assets Valuation Allowance	(6,390)	3,580	280
Income Tax Reconciliation, Tax Reform	0	0	(400)	$ 12,700
Income Tax Reconciliation, Other Adjustments	(1,020)	(1,150)	(600)
Income Tax Expense (Benefit), Continuing Operations	(22,950)	16,320	18,650
Valuation Allowance [Line Items]
Income Tax Reconciliation, Change in Deferred Tax Assets Valuation Allowance	(6,390)	$ 3,580	$ 280
Foreign Tax Authority [Member]
Valuation Allowance [Line Items]
Other Tax Expense (Benefit)	$ (6,400)