EQUITY SECURITIES - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Summary of Investment Holdings [Line Items]
Capital stock par value	$ 100
Book value of investment in FHLB stock	$ 21,500,000	$ 31,200,000
Market-to-market gains (losses)	48,937,000	41,834,000	$ 39,909,000
Equity Securities [Member]
Summary of Investment Holdings [Line Items]
Equity Securities	5,400,000	1,500,000
Market-to-market gains (losses)	100,000	38,000	400
Equity Securities without Readily Determinable Fair Value, Amount	5,300,000	4,900,000
Investment in Federal Home Loan Bank Stock [Member]
Summary of Investment Holdings [Line Items]
Dividend income from FHLB stock	$ 1,400,000	$ 2,000,000.0	$ 2,700,000