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RESTRICTED STOCK - Narrative (Details) - USD ($)	12 Months Ended
RESTRICTED STOCK - Narrative (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 01, 2021
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Restricted stock	$ 37,732,000	$ 60,707,000
FHLBNY
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Share price	$ 100
Bank owned shares	128,184	607,074
Capital stock acquired				$ 13,900,000
Decrease in outstanding FHLBNY advances	$ 1,180,000,000
Dividend income on the FHLBNY capital stock	1,900,000	$ 3,000,000.0	$ 3,600,000
Restricted stock	$ 12,819,000	$ 60,707,000
FRB capital stock
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Share price	$ 50
Bank owned shares	494,965	0
Capital stock acquired				9,300,000
Dividend income on the FHLBNY capital stock	$ 442,000	$ 0	0
Restricted stock	$ 24,748,000
Bankers' Bank capital stock (ACBB)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Bank owned shares	60	0
Capital stock acquired				$ 165,000
Dividend income on the FHLBNY capital stock	$ 1,000	$ 0	$ 0
Restricted stock	$ 165,000
Bankers' Bank capital stock (ACBB) \| Minimum
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Share price	$ 2,500
Bankers' Bank capital stock (ACBB) \| Maximum
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Share price	$ 3,250