Stock Based Compensation - Exercise Price Range (Details) - Stock Options - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options, Outstanding (in shares)	1,222	1,269	1,350
Weighted Average Remaining Contractual Life (In Years)	5 years 9 months 22 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 1.99	$ 1.98	$ 2.02
Number of Options, Exercisable (in shares)	1,198	960	729
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 1.99	$ 1.99	$ 2.05
$0.90 – $1.44
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	0.90
Range of price, upper range limit (in dollars per share)	$ 1.44
Number of Options, Outstanding (in shares)	58
Weighted Average Remaining Contractual Life (In Years)	5 years 9 months 15 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 0.94
Number of Options, Exercisable (in shares)	58
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 0.94
$1.45 – $1.96
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	1.45
Range of price, upper range limit (in dollars per share)	$ 1.96
Number of Options, Outstanding (in shares)	113
Weighted Average Remaining Contractual Life (In Years)	5 years 9 months 15 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 1.55
Number of Options, Exercisable (in shares)	107
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 1.55
$1.97 – $2.04
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	1.97
Range of price, upper range limit (in dollars per share)	$ 2.04
Number of Options, Outstanding (in shares)	881
Weighted Average Remaining Contractual Life (In Years)	6 years 4 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 1.98
Number of Options, Exercisable (in shares)	863
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 1.98
$2.05 – $2.60
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	2.05
Range of price, upper range limit (in dollars per share)	$ 2.60
Number of Options, Outstanding (in shares)	69
Weighted Average Remaining Contractual Life (In Years)	4 years 2 months 12 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 2.25
Number of Options, Exercisable (in shares)	69
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 2.25
$2.61 – $3.02
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of price, lower range limit (in dollars per share)	2.61
Range of price, upper range limit (in dollars per share)	$ 3.02
Number of Options, Outstanding (in shares)	101
Weighted Average Remaining Contractual Life (In Years)	5 years 1 month 28 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 3.02
Number of Options, Exercisable (in shares)	101
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 3.02