Other Comprehensive Income - Summary of Other Comprehensive Income and Tax Impact (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract]
Unrealized gain (loss) on available-for-sale securities, income tax expense (benefit)	$ 116	$ 1	$ 304	$ (121)
Unrealized gain (loss) on interest rate swaps, income tax expense (benefit)	$ (225)	$ 54	$ (358)	$ 193