Income Taxes (Provision for Income Taxes from Continuing Operations Differs from the Federal Statutory Rate) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory rate, amount	$ (29,664)	$ (291)	$ 7,758
Intangible asset impairment, amount	26,637	7,241	1,514
State taxes, less federal effect, amount	606	1,382	1,282
Change in valuation allowance, amount	94	(2,268)	(39)
Federal tax credits, amount	(255)	(517)	(270)
Uncertain tax positions, amount	(169)	(515)	(872)
Foreign rate differential, amount	(311)	(163)	(335)
Non-deductible expenses, amount	173	(66)	366
Other, amount	(69)	(6)	113
Provision for income taxes	$ (2,958)	$ 4,797	$ 9,517
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Statutory rate, percentage	35.00%	35.00%	35.00%
Intangible asset impairment, percentage	(31.40%)	(870.30%)	6.80%
State taxes, less federal effect, percentage	(0.70%)	(166.10%)	5.80%
Change in valuation allowance, percentage	(0.10%)	272.60%	(0.20%)
Federal tax credits, percentage	0.30%	62.10%	(1.20%)
Uncertain tax positions, percentage	0.20%	61.90%	(3.90%)
Foreign rate differential, percentage	0.40%	19.60%	(1.50%)
Non-deductible expenses, percentage	(0.20%)	7.90%	1.70%
Other, percentage	0.00%	0.70%	0.50%
Effective income tax rate, percentage	3.50%	(576.60%)	43.00%