Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 3,369	$ 4,488
Unrecognized compensation expense related to unvested stock-settled awards	$ 34,996
Weighted average period over which unrecognized compensation expense is expected to be recognized (in years)	3 years 3 months 18 days
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 0	6
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	3,219	2,407
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	8	10
Cash-settled performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 142	$ 2,065
Long-Term Incentive Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under the plan	2,550,000

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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