Share-Based Compensation - Components of Awards (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	$ 1,208	$ 1,214	$ 2,398	$ 2,433
Income tax expense (benefit)	(266)	(265)	(575)	(522)
Total share-based compensation expense, net of income taxes	942	949	1,823	1,911
Stock and ESPP Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	40	12	115	53
Income tax expense (benefit)	(20)	(29)	(92)	(29)
Total share-based compensation expense, net of income taxes	20	(17)	23	24
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	1,168	1,202	2,283	2,380
Income tax expense (benefit)	(246)	(236)	(483)	(493)
Total share-based compensation expense, net of income taxes	$ 922	$ 966	$ 1,800	$ 1,887

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

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