Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense		$ 8,200	$ 11,000	$ 8,500
Share-based compensation		8,154	11,021	8,522
Share-based Payment Arrangement, Expense, Tax Benefit		$ 1,900	$ 2,600	$ 1,600
Shares repurchased (in shares)		91,000	28,000	1,200,000
Repurchase of common stock		$ 5,439	$ 1,162	$ 46,580
Number of treasury shares retired (in shares)		0	0	3,900,000
Retirement of treasury stock				$ 0
Additional Paid-In Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Retirement of treasury stock		$ 0	$ 0	$ 199,418
Equity Incentive Award Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)	1,897,809	1,897,809	2,110,598
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense	$ (1,900)	$ 700	$ 1,200

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

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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