Share-Based Compensation - Components of Share-Based Compensation Awards (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	$ 1,135	$ 1,062	$ 3,568	$ 2,887
Income tax expense (benefit)	149	(226)	(373)	(1,008)
Total share-based compensation expense, net of income taxes	1,284	836	3,195	1,879
Stock and ESPP Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	23	36	76	72
Income tax expense (benefit)	0	0	(29)	(57)
Total share-based compensation expense, net of income taxes	23	36	47	15
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	1,112	1,026	3,492	2,815
Income tax expense (benefit)	149	(226)	(344)	(951)
Total share-based compensation expense, net of income taxes	$ 1,261	$ 800	$ 3,148	$ 1,864

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

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