INVESTMENTS - Gross Unrealized Losses and Fair Value by Length of Time of Available-For-Sale Securities (Detail) $ in Thousands	Dec. 31, 2024 USD ($) security	Dec. 31, 2023 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	476	454
Fair Value
Less Than 12 Months	$ 226,115	$ 26,893
12 Months or More	861,065	1,050,289
Total	1,087,180	1,077,182
Unrealized Losses
Less Than 12 Months	3,704	190
12 Months or More	110,030	118,130
Total	$ 113,734	$ 118,320
U.S. treasuries and government agencies
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	7	10
Fair Value
Less Than 12 Months	$ 0	$ 0
12 Months or More	82,314	96,927
Total	82,314	96,927
Unrealized Losses
Less Than 12 Months	0	0
12 Months or More	2,106	4,751
Total	$ 2,106	$ 4,751
State and municipal
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	116	123
Fair Value
Less Than 12 Months	$ 2,979	$ 4,162
12 Months or More	226,234	262,081
Total	229,213	266,243
Unrealized Losses
Less Than 12 Months	213	84
12 Months or More	46,691	43,208
Total	$ 46,904	$ 43,292
Mortgage-backed and asset-backed
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	353	321
Fair Value
Less Than 12 Months	$ 223,136	$ 22,731
12 Months or More	552,517	691,281
Total	775,653	714,012
Unrealized Losses
Less Than 12 Months	3,491	106
12 Months or More	61,233	70,171
Total	$ 64,724	$ 70,277