Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash Flows from Operating Activities
Net income	$ 354,124	$ 360,642	$ 298,304
Adjustments to reconcile net income to net cash provided by operating activities:
Provision/(reversal) for credit losses	25,978	14,543	(16,008)
Provision for losses on other real estate owned	0	0	17
Deferred tax (benefit)/ provision	(4,782)	(2,088)	9,168
Depreciation and amortization	8,371	9,958	7,956
Amortization of right-of-use asset	9,733	9,845	8,160
Change in operating lease liabilities	2,279	(4,629)	(2,790)
Net gains on sale and transfers of other real estate owned	0	(6)	(57)
Net gains on sale of loans	0	(1)	(357)
Proceeds from sales of loans	0	33	5,351
Originations of loans held for sale	0	0	(4,994)
Loss on sales or disposal of fixed assets	6	67	55
Amortization of alternative energy partnerships, venture capital and other investments	86,616	42,065	45,447
Net gain on sales and calls of securities	0	(101)	(853)
Amortization/accretion of security premiums/discount, net	(11,373)	2,465	7,865
Unrealized (gain)/loss on equity securities	(18,248)	(291)	2,036
Write-off of AFS debt securities	3,000	0	0
Stock-based compensation and stock issued to officers as compensation	7,836	7,832	6,810
Net change in accrued interest receivable and other assets	(54,369)	(80,411)	(34,196)
Net change in other liabilities	(24,429)	107,467	2,403
Net cash provided by operating activities	384,742	467,390	334,317
Cash Flows from Investing Activities
Purchase of investment securities available-for-sale	(618,334)	(711,707)	(560,140)
Proceeds from repayment, maturity, and call of investment securities available-for-sale	522,815	213,936	424,386
Proceeds from sale of investment securities available-for-sale	0	0	21,102
Proceeds from sale of equity securities	0	553	0
Benefits received from bank owned life insurance policies	0	4,013	2,752
Purchase of Federal Home Loan Bank stock	(29,381)	(9,776)	0
Redemption of Federal Home Loan Bank stock	28,885	9,776	0
Net increase in loans	(1,327,048)	(1,272,268)	(715,862)
Purchase of premises and equipment	(3,401)	(3,390)	(3,728)
Proceeds from sales of other real estate owned	0	307	795
Net increase in investment in affordable housing and alternative energy partnerships	(50,616)	(6,995)	(29,229)
Acquisitions, net of cash acquired	0	(73,882)	0
Net cash used for investing activities	(1,477,080)	(1,849,433)	(859,924)
Cash Flows from Financing Activities
Increase/(decrease) in deposits	820,041	(128,803)	1,949,728
Advances from Federal Home Loan Bank	14,035,000	5,480,000	50,000
Repayment of Federal Home Loan Bank borrowings	(13,980,000)	(5,015,000)	(180,000)
Cash dividends paid	(98,638)	(100,955)	(99,322)
Purchase of treasury stock	(16,667)	(141,316)	(167,104)
Proceeds from shares issued under Dividend Reinvestment Plan	3,491	3,720	3,563
Taxes paid related to net share settlement of RSUs	(4,490)	(2,905)	(2,632)
Net cash provided by financing activities	758,737	94,741	1,554,233
(Decrease)/increase in cash, cash equivalents, and restricted cash	(333,601)	(1,287,302)	1,028,626
Cash, cash equivalents, and restricted cash, beginning of the year	1,162,402	2,449,704	1,421,078
Cash, cash equivalents, and restricted cash, end of the period	828,801	1,162,402	2,449,704
Supplemental Cash Flow Information
Interest	484,861	105,521	75,486
Income taxes	70,332	96,881	92,691
Non-cash investing and financing activities:
Net change in unrealized holding gain/(loss) on securities available-for-sale, net of tax	18,642	(105,043)	(11,989)
Net change in unrealized holding (loss)/gain on cash flow hedge derivatives	(1,763)	5,813	3,614
Transfers to other real estate owned from loans held-for-investment	15,374	0	205
Loans transferred from held-for-investment to held-for-sale	$ 0	$ 32	$ 0