Income Taxes (Schedule of Provisions of Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current Income Tax Expense (Benefit), Continuing Operations
Federal	$ 42,541	$ 33,655	$ 22,297
State and local	9,165	6,764	6,416
Foreign	839	1,070	1,214
Total current provision	52,545	41,489	29,927
Deferred Income Tax Expense (Benefit), Continuing Operations
Federal	2,342	5,923	12,478
State and local	(671)	(969)	1,639
Foreign	(3,175)	(1,538)	(243)
Total deferred provision	(1,504)	3,416	13,874
Provision for income taxes	$ 51,041	$ 44,905	$ 43,801