Income Taxes (Components of Provision for Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current provision:
State	$ 5,520	$ 5,764	$ 5,513
Foreign	18,150	13,756	11,681
Total current	23,670	19,520	17,194
Deferred provision (benefit) for taxes:
Federal	(3,306)	(9,463)	18,736
State	1,952	(1,412)	(241)
Foreign	13,138	(16,673)	9,155
Change in valuation allowance	4,151	12,261	(31,607)
Total deferred	15,935	(15,287)	(3,957)
Total provision for income taxes	$ 39,605	$ 4,233	$ 13,237