Income Taxes (Components Of Income Tax Provision) (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Abstract]
Current: U.S. federal													$ (2,110)	$ 10,753	$ 23,336
Current: State													30	169	72
Current: Foreign													8,099	925	6,588
Current: Total													6,019	11,847	29,996
Deferred: U.S. federal													(1,245)	(5,252)	(21,624)
Deferred: State														(225)	(87)
Deferred: Foreign													(5,321)	2,602	(2,844)
Deferred: Total													(6,566)	(2,875)	(24,555)
Total income tax (benefit) provision	$ (1,212)	$ (2,214)	$ 1,700	$ 1,179	$ 29,535	$ (3,524)	$ (10,096)	$ (6,943)	$ 75	$ 1,113	$ 694	$ 3,559	$ (547)	$ 8,972	$ 5,441