CONDENSED HOLDING COMPANY ONLY FINANCIAL STATEMENTS - CONDENSED STATEMENTS OF CASH FLOWS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Adjustments to reconcile net income to net cash provided by operating activities:
Net gain on marketable equity securities	$ (131)	$ (361)	$ (531)
Decrease (increase) in other assets	118,641	(13,106)	3,186
Increase in other liabilities	(118,333)	(11,578)	(3,336)
Net cash provided by operating activities	146,327	59,932	68,491
Cash flows from Investing Activities:
Proceeds from sales of marketable equity securities	6,101	546	570
Purchases of investment securities available-for-sale and marketable equity securities	0	(261)	(266)
Net cash received in business combination	715,988
Net cash provided by (used in) investing activities	1,102,821	(324,385)	(10,365)
Cash flows from Financing Activities:
Proceeds from preferred stock issuance, net		116,569
Proceeds from exercise of stock options	431	38	367
Release of stock for benefit plan awards	1,153	84	131
Payments related to tax withholding for equity awards	(111)	(3,060)	(133)
BMP ESOP shares received to satisfy distribution of retirement benefits	(993)		(4)
Treasury shares repurchased	(59,280)	(35,356)	(24,191)
Cash dividends paid to preferred stockholders	(7,286)	(4,783)
Cash dividends paid to common stockholders	(39,351)	(18,711)	(20,082)
Net cash (used in) provided by financing activities	(1,099,029)	352,568	(49,894)
Increase (decrease) in cash and cash equivalents	150,119	88,115	8,232
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	243,603	155,488	147,256
CASH AND CASH EQUIVALENTS, END OF PERIOD	393,722	243,603	155,488
Parent Company
Cash flows from Operating Activities:
Net income	103,996	42,318	36,186
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings of subsidiaries	(92,597)	(16,461)	12,480
Net gain on marketable equity securities	(131)	(361)	(531)
Net accretion	(157)	146	147
Decrease (increase) in other assets	761	(502)	26
Increase in other liabilities	269	214	388
Net cash provided by operating activities	12,141	25,354	48,696
Cash flows from Investing Activities:
Proceeds from sales of marketable equity securities	6,101	546	570
Purchases of investment securities available-for-sale and marketable equity securities	(3,000)	(261)	(266)
Reimbursement from subsidiary, including purchases of investment securities available-for-sale		2	26
Net cash received in business combination	11,545
Net cash provided by (used in) investing activities	14,646	287	330
Cash flows from Financing Activities:
Redemption of preferred stock		(3)	(1)
Proceeds from preferred stock issuance, net		116,569
Proceeds from exercise of stock options	431	38	367
Release of stock for benefit plan awards	1,153	84	131
Payments related to tax withholding for equity awards	(111)	(3,060)	(133)
BMP ESOP shares received to satisfy distribution of retirement benefits	(993)		(4)
Treasury shares repurchased	(59,280)	(35,356)	(24,191)
Cash dividends paid to preferred stockholders	(7,286)	(4,783)
Cash dividends paid to common stockholders	(39,351)	(18,696)	(20,082)
Net cash (used in) provided by financing activities	(105,437)	54,793	(43,913)
Increase (decrease) in cash and cash equivalents	(78,650)	80,434	5,113
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	106,014	25,580	20,467
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 27,364	$ 106,014	$ 25,580