Income Taxes (Benefit of) Provision for Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Benefit of income taxes	$ (239)	$ (26)	$ (16)
Deferred:
Total deferred	(7,105)	(4,893)	(2,051)
Provision for income taxes	14,943	16,264	13,624
Continuing Operations
Current:
U.S. Federal	16,882	14,703	12,294
State	2,479	2,987	2,010
Foreign	2,687	3,467	1,371
Total current	22,048	21,157	15,675
Deferred:
U.S. Federal	(7,466)	(5,404)	(178)
State	1,246	1,595	273
Foreign	(885)	(1,084)	(2,146)
Total deferred	(7,105)	(4,893)	(2,051)
Provision for income taxes	14,943	16,264	13,624
Discontinued Operations
Current:
U.S. Federal	219	24	15
State	20	2	1
Foreign	0	0	0
Benefit of income taxes	$ 239	$ 26	$ 16