Stock-based Compensation - Summary of Information Related to Stock Option Plan (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash received from option exercises			$ 89	$ 305
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised	$ 0	$ 0	174	370
Cash received from option exercises	0	0	64	63
Tax benefit realized from option exercised	0	0	20	17
2010 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised	0	0	86	608
Cash received from option exercises	0	0	25	242
Tax benefit realized from option exercised	0	0	0	157
2010 Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Tax benefit (provision) realized from awards vested	$ 0	$ 24	$ (85)	$ 21

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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