CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
INTEREST INCOME:
Loans receivable	$ 577,891,000	$ 450,916,000	$ 445,731,000
Mortgage-backed securities	72,352,000	67,585,000	45,723,000
Securities and cash equivalents	51,329,000	54,068,000	29,046,000
Total interest income	701,572,000	572,569,000	520,500,000
INTEREST EXPENSE:
Deposits	100,126,000	10,124,000	11,770,000
FHLB advances	10,524,000	489,000	2,592,000
Other borrowings	3,376,000	377,000	467,000
Subordinated debt	11,541,000	8,400,000	8,780,000
Total interest expense	125,567,000	19,390,000	23,609,000
Net interest income	576,005,000	553,179,000	496,891,000
Financing Receivable, Credit Loss, Expense (Reversal)	10,789,000	10,364,000	(33,388,000)
Interest Income (Expense), after Provision for Loan Loss, Total	565,216,000	542,815,000	530,279,000
NON-INTEREST INCOME
Deposit fees and other service charges	41,638,000	44,459,000	39,495,000
Mortgage banking operations	11,817,000	10,834,000	33,948,000
Bank Owned Life Insurance Income	9,245,000	7,794,000	5,000,000
Miscellaneous	5,169,000	6,805,000	12,875,000
Other operating income	67,869,000	69,892,000	91,318,000
Net (loss) gain on sale of securities	(19,242,000)	(3,248,000)	482,000
Net change in valuation of financial instruments carried at fair value	(4,218,000)	807,000	4,616,000
Gain on sale of branches, including related deposits	0	7,804,000	0
Total non-interest income	44,409,000	75,255,000	96,416,000
NON-INTEREST EXPENSE:
Salary and employee benefits	244,563,000	242,266,000	244,351,000
Less capitalized loan origination costs	(16,257,000)	(24,313,000)	(34,401,000)
Occupancy and equipment	47,886,000	52,018,000	52,850,000
Information and computer data services	28,445,000	25,986,000	24,356,000
Payment and card processing services	20,547,000	21,195,000	20,544,000
Professional and legal expenses	9,830,000	14,005,000	22,274,000
Advertising and marketing	4,794,000	3,959,000	6,036,000
Deposit insurance	10,529,000	6,649,000	5,583,000
State and municipal business and use taxes	5,260,000	4,693,000	4,343,000
Real estate operations, net	(538,000)	(104,000)	(22,000)
Amortization of core deposit intangibles	3,756,000	5,279,000	6,571,000
Loss on extinguishment of debt	0	793,000	2,284,000
Miscellaneous	23,723,000	24,869,000	24,236,000
Total other operating expense, before acquisition related costs	382,538,000	377,295,000	379,005,000
COVID-19 expenses	0	0	436,000
Merger and acquisition - related expenses	0	0	660,000
Total non-interest expense	382,538,000	377,295,000	380,101,000
Income before provision for income taxes	227,087,000	240,775,000	246,594,000
PROVISION FOR INCOME TAXES	43,463,000	45,397,000	45,546,000
NET INCOME	$ 183,624,000	$ 195,378,000	$ 201,048,000
Earnings per common share:
Basic (in dollars per share)	$ 5.35	$ 5.70	$ 5.81
Diluted (in dollars per share)	5.33	5.67	5.76
Cumulative dividends declared per common share (in dollars per share)	$ 1.92	$ 1.76	$ 1.64
Weighted average number of common shares outstanding:
Basic	34,344,142	34,264,322	34,610,056
Diluted	34,450,412	34,459,922	34,919,188