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Stock-Based Awards - Additional Information (Detail) $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 20, 2016 shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) Employee shares	Dec. 31, 2016 shares
Share-based Payment Award
Stock option issuance period		10 years
Option vested period		1 year
Shares of common stock authorized to issue under equity award plan \| shares	10,000,000
Stock-based compensation expense		$ 11,590	$ 13,255	$ 14,717
Tax benefit realized for the tax deductions for share-based compensation		1,649	2,364	7,684
Stock-based compensation expense as a result of modification to accelerate vesting of certain awards				$ 525
Number of employees to which modification to accelerate vesting of certain awards was made \| Employee				20
Total intrinsic value of options exercised		301	4,218	$ 1,643
Cash received from option exercise		$ 160	$ 191	$ 532
Outstanding options \| shares		485,536	570,537	1,158,828	1,368,247
Options remaining average contractual term		10 months 24 days
Options intrinsic value		$ 297
Below 25th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		0.00%
At 25th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		50.00%
At 50th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		100.00%
At 100th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		200.00%
Income Tax Expense Benefit [Member]
Share-based Payment Award
Tax benefit realized for the tax deductions for share-based compensation		$ 2,791	$ 3,015	$ 5,402
Performance Based Restricted Stock Unit [Member] \| Maximum [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		200.00%
Performance Based Restricted Stock Unit [Member] \| Minimum [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		0.00%