Stock-Based Compensation Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement [Line Items]
Stock options terms (in years)			10 years
Stock-based compensation expense	$ 1,570	$ 1,552	$ 3,339	$ 4,808
Stock-based compensation expense, net of tax benefit	$ 942	$ 1,016	$ 27	$ 3,197
Directors' Plan [Member]
Statement [Line Items]
Shares reserved for future grants under the stock option and compensation plan	360,000		360,000
Employee Equity Plan [Member]
Statement [Line Items]
Awards vesting period (in years)			3 years
Shares reserved for future grants under the stock option and compensation plan	11,097,554		11,097,554