Equity Compensation - Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 4,051	$ 777	$ 1,834
Selling, general and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	11,110	5,283	7,347
Selling, general and administrative expense | Non-qualified stock options
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	1,939	201	865
Selling, general and administrative expense | Restricted stock and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	4,772	4,305	4,648
Selling, general and administrative expense | Performance shares and performance share units
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 4,399	$ 777	$ 1,834