Stock-based Compensation Plans and Awards - Stock Options Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Stock option activity
Outstanding beginning balance (in shares)	1,853
Options granted (in shares)	120
Options exercised (in shares)	(105)
Options forfeited or cancelled (in shares)	(58)
Outstanding ending balance (in shares)	1,810	1,853
Exercisable (in shares)	1,671
Vested and expected to vest (in shares)	1,810
Weighted average exercise price
Outstanding beginning balance (in dollars per share)	$ 9.65
Options granted (in dollars per share)	7.80
Options exercised (in dollars per share)	5.70
Options forfeited or canceled (in dollars per share)	5.90
Outstanding ending balance (in dollars per share)	9.88	$ 9.65
Exercisable (in dollars per share)	10.02
Vested and expected to vest (in dollars per share)	$ 9.88
Weighted average remaining contractual term (in years)
Options outstanding	5 years 3 months 22 days	6 years 1 month 2 days
Exercisable	5 years 4 days
Vested and expected to vest	5 years 3 months 22 days
Aggregate intrinsic value
Options outstanding (in dollars)		$ 879