Description of Business and Summary of Significant Accounting Policies Advertising Costs (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Advertising Costs [Abstract]
Advertising Expense	$ 4,400	$ 4,700
Capitalized Direct Response Advertising Costs [Line Items]
Capitalized Direct Response Advertising Costs, net	2,400		$ 2,800
Capital Direct Response Advertising, Amortization	$ 3,000	$ 3,100
Minimum [Member]
Capitalized Direct Response Advertising Costs [Line Items]
Capitalized Direct Response Advertising Costs, Amortization Period	12 months
Maximum [Member]
Capitalized Direct Response Advertising Costs [Line Items]
Capitalized Direct Response Advertising Costs, Amortization Period	24 months