INVESTMENTS - Gross Unrealized Losses and Fair Value by Length of Time of Available-For-Sale Securities (Detail) $ in Thousands	Dec. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	464	141
Fair Value
Less Than 12 Months	$ 779,965	$ 778,714
12 Months or More	400,181	59,597
Total	1,180,146	838,311
Unrealized Losses
Less Than 12 Months	79,408	12,583
12 Months or More	72,974	2,837
Total	$ 152,382	$ 15,420
U.S. treasuries and government agencies
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	10	5
Fair Value
Less Than 12 Months	$ 53,139	$ 49,695
12 Months or More	40,483	0
Total	93,622	49,695
Unrealized Losses
Less Than 12 Months	3,653	150
12 Months or More	3,651	0
Total	$ 7,304	$ 150
State and municipal
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	130	32
Fair Value
Less Than 12 Months	$ 200,439	$ 63,206
12 Months or More	62,482	21,740
Total	262,921	84,946
Unrealized Losses
Less Than 12 Months	30,803	2,288
12 Months or More	25,723	1,157
Total	$ 56,526	$ 3,445
Mortgage-backed and asset-backed
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	324	104
Fair Value
Less Than 12 Months	$ 526,387	$ 665,813
12 Months or More	297,216	37,857
Total	823,603	703,670
Unrealized Losses
Less Than 12 Months	44,952	10,145
12 Months or More	43,600	1,680
Total	$ 88,552	$ 11,825