COMMITMENTS AND CONTINGENCIES - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Commitments and Contingencies Disclosure [Line Items]
Reserves for unfunded commitments	$ 16,700	$ 16,700	$ 13,400
Loans and Leases Receivable, Commitments, Fixed Rates		127,400	129,200
Loans and Leases Receivable, Commitments, Variable Rates		$ 4,100,000	$ 3,800,000
Loan Commitments, Fixed Interest Rate Range, Minimum		0.00%	0.00%
Loan Commitments, Fixed Interest Rate Range, Maximum		21.00%	21.00%
Loan Commitments, Fixed Rate, Maturities, Minimum		1 year	1 year
Loan Commitments, Fixed Rate, Maturities, Maximum		30 years 10 months 24 days	30 years 10 months 24 days
Letters of credit issued to guarantee performance of a client to a third party	35,100	$ 35,100	$ 41,100
Derivative, Notional Amount	17,687,419	17,687,419	17,683,691
Litigation Settlement, Expense	0	3,300	7,100
Estimated Litigation Liability	0	0	0
Credit Default Swap
Commitments and Contingencies Disclosure [Line Items]
Derivative, Notional Amount	381,100	381,100	362,800
Commitments to Extend Credit
Commitments and Contingencies Disclosure [Line Items]
Commitments outstanding to extend credit	$ 4,200,000	$ 4,200,000	$ 4,000,000