Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Cash Flows from Operating Activities
Net income	$ 99,035	$ 72,397	$ 263,041	$ 222,980
Adjustments to reconcile net income to net cash provided by operating activities:
Provision/(reversal) for credit losses	2,000	3,050	13,143	(19,508)
Provision for losses on other real estate owned			0	(8)
Deferred tax (benefit)/provision			(713)	8,867
Depreciation and amortization			6,847	5,942
Amortization of right-of-use asset			7,446	5,972
Change in operating lease liabilities			(3,216)	(1,456)
Net gains on sale and transfer of other real estate owned			(6)	(120)
Net gains on sale of loans			(1)	(357)
Proceeds from sales of loans			33	5,351
Originations of loans held for sale			0	(4,994)
Loss on sales or disposal of fixed assets			46	55
Amortization on alternative energy partnerships, venture capital and other investments			27,471	31,610
Net gain on sales and calls of securities			(101)	(853)
Amortization/accretion of security premiums/discounts, net			2,875	6,128
Unrealized (gain)/loss on equity securities	3,700	(3,000)	(1,257)	3,628
Stock-based compensation and stock issued to officers as compensation			6,032	4,999
Net change in accrued interest receivable and other assets			(77,012)	(21,607)
Net change in other liabilities			125,345	(9,082)
Net cash provided by operating activities			369,973	237,547
Cash Flows from Investing Activities
Purchase of investment securities available-for-sale			(583,992)	(406,750)
Proceeds from repayments, maturities and calls of investment securities available-for-sale			130,673	326,527
Proceeds from sale of investment securities available-for-sale			553	21,102
Net increase in loans			(1,122,519)	(349,924)
Purchase of premises and equipment			(3,093)	(2,828)
Benefits received from bank owned life insurance policies			0	2,752
Proceeds from sales of other real estate owned			307	0
Net increase in investment in affordable housing and alternative energy partnerships			(107)	(19,039)
Acquisition, net of cash acquired			(73,882)	0
Net cash used for investing activities			(1,652,060)	(428,160)
Cash Flows from Financing Activities
Net (decrease)/increase in deposits			(58,316)	897,713
Advances from Federal Home Loan Bank			340,000	50,000
Repayment of Federal Home Loan Bank borrowings			0	(180,000)
Cash dividends paid			(76,111)	(73,335)
Purchases of treasury stock			(109,774)	(100,668)
Proceeds from shares issued under Dividend Reinvestment Plan			2,793	2,619
Taxes paid related to net share settlement of RSUs			(2,864)	(2,632)
Net cash provided by financing activities			95,728	593,697
(Decrease)/Increase in cash, cash equivalents, and restricted cash			(1,186,359)	403,084
Cash, cash equivalents, and restricted cash, beginning of the period			2,449,704	1,421,078	$ 1,421,078
Cash, cash equivalents, and restricted cash, end of the period	$ 1,263,345	$ 1,824,162	1,263,345	1,824,162	$ 2,449,704
Supplemental disclosure of cash flow information
Interest			52,147	61,574
Income taxes paid			59,981	65,291
Non-cash investing and financing activities:
Net change in unrealized holding loss on securities available-for-sale, net of tax			(115,612)	(7,872)
Net change in unrealized holding gain on cash flow hedge derivatives			5,803	2,194
Loans transferred from held-for-investment to held-for-sale			32	0
Transfers to other real estate owned from loans held for investment			$ 0	$ 205