Income Taxes (Change in Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 3,521	$ 431	$ 378
Additions based on tax positions related to the current year	435	382	293
Additions for tax positions of prior years	1,735	3,001	0
Reductions for tax positions of prior years	(468)	(293)	0
Changes due to lapse of statute of limitations	279	0	(240)
Reductions due to settlements with tax authorities	(495)	0	0
Ending balance	$ 5,007	$ 3,521	$ 431