Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Effective income tax rate	12.10%	18.10%	17.60%
Income taxes paid	$ 110,700	$ 88,000	$ 69,700
Income tax ruling exemption	14,200	13,700	9,200
Valuation allowance	40,262	9,454	6,212	$ 6,211
Net operating loss carryforwards in certain state and international jurisdictions	23,100
Unrecognized tax benefits	22,484	26,841	24,247	$ 21,417
Unrecognized tax benefits that would impact effective tax rate if recognized	21,800	21,200
Interest expense and penalties related to unrecognized tax benefits	1,300	1,800	1,200
Interest expense and penalties accrued	$ 3,600	$ 3,600	$ 2,100