Employee Stock-Based Compensation - Option Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, beginning balance (in shares) | shares	251
Options, exercised in period (in shares) | shares	(70)
Options outstanding, ending balance (in shares) | shares	181
Options, exercisable (in shares) | shares	181
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Options outstanding, beginning balance, weighted average exercise price (in USD per share) | $ / shares	$ 20.63
Options, exercises in period, weighted average exercise price (in USD per share) | $ / shares	22.01
Options outstanding, ending balance, weighted average exercise price (in USD per share) | $ / shares	20.09
Options, exercisable, weighted average exercise price (in USD per share) | $ / shares	$ 20.09
Options, outstanding, weighted average remaining contractual term	2 years 4 months 17 days
Options, exercisable, weighted average remaining contractual term	2 years 4 months 17 days
Options, outstanding, intrinsic value | $	$ 814
Options, exercisable, intrinsic value | $	$ 814