Income Taxes - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019 USD ($) Tax_Positions	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Income Tax Contingency [Line Items]
Valuation allowance	$ 2,988,000	$ 3,015,000
Income tax expense (benefit)	$ 44,964,000	42,289,000	$ 46,791,000
Unrecognized tax benefits number of tax matters | Tax_Positions	0
Unrecognized tax benefits related to identified uncertain tax positions	$ 0
Tax years subject to examination	2015 2016 2017
Accounting Standards Update 2016-09 [Member]
Income Tax Contingency [Line Items]
Income tax expense (benefit)	$ 3,500,000	$ 2,400,000	$ 1,500,000