Stock-Based Compensation - Summarized Information for the Plans (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, Beginning Balance (in shares)	268,802
Granted (in shares)	0
Exercised (in shares)	(24,774)
Expired (in shares)	0
Canceled (in shares)	(5,280)
Outstanding, Ending Balance (in shares)	238,748	268,802
Exercisable, Ending Balance (in shares)	238,748
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price, Outstanding, Beginning Balance (in dollars per share)	$ 22.27
Granted (in dollars per share)	0
Exercised (in dollars per share)	12.50
Expired (in dollars per share)	0
Canceled (in dollars per share)	21.72
Weighted Average Exercise Price, Outstanding, Ending Balance (in dollars per share)	23.30	$ 22.27
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 23.30
Aggregate Intrinsic Value, Outstanding	$ 2,157
Aggregate Intrinsic Value, Exercisable	$ 2,157
Granted (in dollars per share)	$ 0	$ 0	$ 0
Aggregate intrinsic value of options exercised	$ 425	$ 298	$ 4,194
Weighted average grant-date fair value of shares vested	$ 0	$ 0	$ 1,400

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Period Type:	instant

- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.