Income Taxes (Schedule of Components of Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current expense:
Federal	$ 81,459	$ 80,360	$ 162,639
State	12,657	13,663	14,301
Foreign	24,608	25,001	17,382
Current expense (benefit)	118,724	119,024	194,322
Deferred expense (benefit):
Federal	(2,216)	34,636	(38,416)
State	(98)	3,627	(2,436)
Foreign	(36,602)	(4,896)	(7,813)
Deferred expense (benefit)	(38,916)	33,367	(48,665)
Tax expense (benefit) relating to uncertain tax positions, including accrued interest	(1,338)	3,915	5,084
Income tax expense	$ 78,470	$ 156,306	$ 150,741