Stock-Based Compensation - Restricted and Performance Unit Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Allocated share-based compensation expense	$ 5,300	$ 3,700	$ 3,200
Total compensation cost not yet recognized	$ 12,900
Retricted and performance unit activity
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding - beginning of the period (in shares)	478,891
Granted (in shares)	784,728
Vested (in shares)	(119,147)
Forfeited (in shares)	(108,728)
Outstanding - end of the period (in shares)	1,035,744	478,891
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding - beginning of the period, weighted-average grant date fair value (in dollars per share)	$ 16.37
Granted, weighted-average grant date fair value (in dollars per share)	13.20
Vested, weighted-average grant date fair value (in dollars per share)	16.91
Forfeited, weighted-average grant date fair value (in dollars per share)	14.70
Outstanding - end of the period, weighted-average grant date fair value (in dollars per share)	$ 14.08	$ 16.37
Restricted And Performance Unit Activity [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Equity instruments other than options, vested in period	$ 1,600	$ 2,700	$ 2,700
Stock options
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Total compensation cost not yet recognized, period for recognition	2 years
Employee Stock Purchase Plan (ESPP) [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount to closing price	10.00%
Maximum employee subscription rate, percent of participating employee's base salary	20.00%
Cap, Amount of stock value based on grant date	$ 25
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Employee Stock Ownership Plan (ESOP), Compensation Expense	$ 217	$ 319