Stock-based Compensation - Summary of Information Related to Stock Option Plan (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash received from option exercises			$ 364	$ 514
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised	$ 206	$ 234	593	487
Cash received from option exercises	72	119	179	195
Tax benefit realized from option exercised	5		5
2010 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised			1,090	876
Cash received from option exercises			185	319
Tax benefit realized from option exercised			285	160
2010 Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Tax benefit realized from awards vested	$ 141	$ 272	$ 144	$ 285

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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