Comprehensive Income (Loss) - Summary of Changes in Components of Other Comprehensive Income, Net of Tax (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	$ 1,131,702	$ 1,090,145	$ 1,108,587	$ 827,014
Other comprehensive loss, net of tax	(9,694)	(28,109)	(11,365)	(79,045)
Balance at end of period	1,135,627	1,082,406	1,135,627	1,082,406
Total
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	(76,432)	(47,672)	(74,761)	3,264
Other comprehensive loss, net of tax	(9,694)	(28,109)	(11,365)	(79,045)
Balance at end of period	(86,126)	(75,781)	(86,126)	(75,781)
Unrealized Losses on Available for  Sale Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	(78,147)	(49,908)	(76,729)	745
Other comprehensive loss, net of tax	(9,583)	(27,972)	(11,001)	(78,625)
Net current period other comprehensive loss	(9,583)	(27,972)	(11,001)	(78,625)
Balance at end of period	(87,730)	(77,880)	(87,730)	(77,880)
Unrealized gains on derivatives
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at end of period		2,099		2,099
Amortization of Gain on Debt Securities Reclassified to Held to Maturity
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	1,715	2,236	1,968	2,519
Other comprehensive loss, net of tax	(111)	(137)	(364)	(420)
Balance at end of period	$ 1,604	$ 2,099	$ 1,604	$ 2,099