Income Taxes (Reconciliation of Gross Unrecognized Tax Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of gross unrecognized tax benefits
Gross unrecognized tax benefit balance at beginning of year	$ 3,612	$ 7,636	$ 5,459
Change in tax positions of prior years	3,543		426
Change in tax positions of prior years		(3,073)
Change in tax positions of current year	419	169	2,929
Reduction in tax positions for statute expirations		(1,120)	(1,178)
Gross unrecognized tax benefit balance at end of year	$ 7,574	$ 3,612	$ 7,636