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Income Taxes - Narratives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency
Net operating loss carry forward, foreign	$ 49,700
Deferred income taxes	179,309	$ 173,115
Accrued interest related to uncertain tax positions	1,600	1,400
Income taxes paid	35,300	23,200	$ 16,700
Other assets
Income Tax Contingency
Deferred income taxes	8,900	$ 7,900
Federal
Income Tax Contingency
Net operating loss carry forward	66,400
State and local
Income Tax Contingency
Net operating loss carry forward	27,800
Adjustment
Income Tax Contingency
Current Income Tax Expense (Benefit)	$ (6,300)
Senior Unsecured Notes \| 2.25% Senior Notes due 2024
Income Tax Contingency
Debt instrument stated interest rate (percentage)	2.25%