Income Taxes - Components Of Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes
U.S. federal, Current	$ (493)	$ 8,005	$ 19,590
State and local, Current	1,657	4,386	4,495
Foreign, Current	5,842	4,345	4,264
Total current	7,006	16,736	28,349
U.S. federal, Deferred	732	9,857	6,890
State and local, Deferred	874	1,966	1,226
Foreign, Deferred	(17,904)	(1,937)	2,877
Deferred Income Tax Expense (Benefit), Total	(16,298)	9,886	10,993
Total income tax (benefit) expense	$ (9,292)	$ 26,622	$ 39,342