Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Number of Shares
Options outstanding, beginning balance (in shares)	1,342,000
Options granted (in shares)	0	0
Options exercised (in shares)	(17,000)
Options cancelled/forfeited (in shares)	(55,000)
Options outstanding, ending balance (in shares)	1,270,000		1,342,000
Weighted Average Exercise Price per Share
Options outstanding, weighted average exercise price, beginning balance (in dollars per share)	$ 11.84
Options granted, weighted average exercise price (in dollars per share)	0
Options exercised, weighted average exercise price (in dollars per share)	5.77
Options cancelled/forfeited, weighted average exercise price (in dollars per share)	23.80
Options outstanding, weighted average exercise price, ending balance (in dollars per share)	$ 11.39		$ 11.84
Weighted average remaining contractual life, in years	5 years 7 months 6 days		5 years 10 months 24 days
Stock Options
Weighted Average Exercise Price per Share
Stock-based compensation expense		$ 0.2
PSOs | 2017 Performance Metric, Targeted Free Cash Flow Performance Metric
Weighted Average Exercise Price per Share
Share-based compensation options vested (in shares)	77,000		40,000
Percent of achievement of award target performance metric	95.00%		115.00%