CONDENSED HOLDING COMPANY ONLY FINANCIAL STATEMENTS - CONDENSED STATEMENTS OF CASH FLOWS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Adjustments to reconcile net income to net cash provided by operating activities:
Net gain on marketable equity securities	$ 758		$ (131)
Loss on extinguishment of debt		$ 740	1,751
(Increase) decrease in other assets	10,332	(35,170)	125,486
(Decrease) increase in other liabilities	(45,957)	145,425	(118,333)
Net cash provided by operating activities	90,874	295,172	146,327
Cash flows from Investing Activities:
Proceeds from sales of marketable equity securities			6,101
Purchases of securities available-for-sale	(86,084)	(39,232)	(1,095,028)
Net cash received in business combination			715,988
Net cash used in investing activities	(214,046)	(1,332,191)	1,102,821
Cash flows from Financing Activities:
Proceeds from subordinated debentures issuance, net		157,559
Redemption of subordinated debentures		(155,000)
Proceeds from exercise of stock options			431
Release of stock for benefit plan awards	1,164	1,167	1,153
Payments related to tax withholding for equity awards	(1,258)	(1,558)	(111)
BMP ESOP shares received to satisfy distribution of retirement benefits			(993)
Treasury shares repurchased	(947)	(46,762)	(59,280)
Cash dividends paid to preferred stockholders	(7,286)	(7,286)	(7,286)
Cash dividends paid to common stockholders	(37,302)	(36,791)	(39,351)
Net cash provided by financing activities	411,422	812,594	(1,099,029)
Increase (decrease) in cash and cash equivalents	288,250	(224,425)	150,119
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	169,297	393,722	243,603
CASH AND CASH EQUIVALENTS, END OF PERIOD	457,547	169,297	393,722
Parent Company
Cash flows from operating activities:
Net income	96,094	152,556	103,996
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings of subsidiaries	(39,280)	(65,669)	(92,597)
Net gain on marketable equity securities			(131)
Net accretion	(87)	(111)	(157)
Loss on extinguishment of debt		740
(Increase) decrease in other assets	(62)	(104)	761
(Decrease) increase in other liabilities	(931)	(1,096)	269
Net cash provided by operating activities	55,734	86,316	12,141
Cash flows from Investing Activities:
Proceeds from sales of marketable equity securities			6,101
Purchases of securities available-for-sale			(3,000)
Net cash received in business combination			11,545
Net cash used in investing activities			14,646
Cash flows from Financing Activities:
Proceeds from subordinated debentures issuance, net		157,559
Redemption of subordinated debentures		(155,000)
Proceeds from exercise of stock options			431
Release of stock for benefit plan awards	1,164	1,167	1,153
Payments related to tax withholding for equity awards	(1,258)	(1,558)	(111)
BMP ESOP shares received to satisfy distribution of retirement benefits			(993)
Treasury shares repurchased	(947)	(46,762)	(59,280)
Cash dividends paid to preferred stockholders	(7,286)	(7,286)	(7,286)
Cash dividends paid to common stockholders	(37,302)	(36,791)	(39,351)
Net cash provided by financing activities	(45,629)	(88,671)	(105,437)
Increase (decrease) in cash and cash equivalents	10,105	(2,355)	(78,650)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	25,009	27,364	106,014
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 35,114	$ 25,009	$ 27,364