Stock-based Compensation - Summary of Information Related to Stock Option Plan (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash received from option exercises	$ 380	$ 563	$ 714
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised	370	592	634
Cash received from option exercises	63	179	195
Tax benefit realized from option exercised	17	5
2010 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised	729	1,728	1,338
Cash received from option exercises	317	385	519
Tax benefit realized from option exercised	157	453	286
2010 Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Tax benefit realized from awards vested	$ 21	$ 144	$ 291

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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