Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net earnings (loss)	$ 423,613	$ 606,959	$ (1,237,574)
Goodwill impairment	29,000	0	1,470,000
Depreciation and amortization	53,595	52,195	44,839
Amortization of net premiums on investment securities	52,749	44,197	16,311
Intangible asset amortization	13,576	12,734	14,753
Amortization of operating lease ROU assets	30,228	30,406	29,432
Provision for credit losses	24,500	(162,000)	339,000
Gain on sale of foreclosed assets, net	(3,470)	(406)	(495)
Provision for losses on foreclosed assets	29	14	267
Gain on sale of loans and leases, net	(518)	(1,733)	(2,139)
Loss on sale of premises and equipment	104	74	346
Loss (gain) on sale of securities, net	50,321	(1,615)	(13,171)
Gain on BOLI death benefits	0	(491)	0
credit-linked notes, net	(1,089)	(1,134)	66
Increase in other assets	(83,666)	(97,181)	(105,749)
Increase (decrease) in accrued interest payable and other liabilities	78,231	(11,286)	(96,376)
Net cash provided by operating activities	701,972	502,956	483,873
Cash flows from investing activities:
Cash acquired in acquisitions, net of cash consideration paid	0	3,757,122	0
Net increase in loans and leases	(5,816,608)	(3,925,829)	(463,643)
Proceeds from sales of loans and leases	72,214	144,550	128,138
Proceeds from maturities and paydowns of securities available-for-sale	658,719	847,472	439,473
Proceeds from sales of securities available-for-sale	2,013,094	367,348	173,425
Purchases of securities available-for-sale	(380,251)	(6,863,950)	(1,924,917)
Proceeds from maturities and paydowns of securities held-to-maturity	851	0	0
Net (purchases) redemptions of Federal Home Loan Bank stock	(17,040)	0	23,674
Proceeds from sales of foreclosed assets	19,247	2,638	1,396
Purchases of premises and equipment, net	(20,128)	(17,262)	(12,529)
Proceeds from sales of premises and equipment	11	95	8
Proceeds from BOLI death benefits	555	4,143	761
Net increase in equipment leased to others under operating leases	(100,734)	(30,786)	(46,765)
Net cash used in investing activities	(3,570,070)	(5,714,459)	(1,680,979)
Cash flows from financing activities:
Net (decrease) increase in noninterest-bearing deposits	(3,330,776)	3,726,157	1,952,116
Net increase in interest-bearing deposits	2,269,353	2,170,769	3,757,152
Net increase (decrease) in borrowings	1,763,119	(55,210)	(1,754,008)
Net proceeds from preferred stock offering	498,516	0	0
Common stock repurchased and restricted stock surrendered	(9,531)	(8,505)	(75,369)
Preferred stock dividends paid	(19,339)	0	0
Common stock dividends paid	(120,256)	(119,443)	(159,748)
Net cash provided by financing activities	1,051,086	6,108,076	3,720,143
Net (decrease) increase in cash and cash equivalents	(1,817,012)	896,573	2,523,037
Cash and cash equivalents, beginning of year	4,057,234	3,160,661	637,624
Cash and cash equivalents, end of year	2,240,222	4,057,234	3,160,661
Supplemental disclosures of cash flow information:
Cash paid for interest	238,377	53,446	99,605
Cash paid for income taxes	97,254	136,015	114,235
Loans transferred to foreclosed assets	7,985	1,062	14,755
Transfers from loans held for investment to loans held for sale	76,253	25,554	0
Transfer of securities available-for-sale to held-to-maturity	2,260,407	0	0
Fair value of assets acquired	41,228,936	40,443,344
Liabilities assumed	37,278,405	36,443,714
Civic Acquisition
Supplemental disclosures of cash flow information:
Cash paid		(160,420)
Parent [Member]
Cash flows from operating activities:
Earned stock compensation	34,769	32,223	24,363
Increase in other assets	(323,852)	(67,242)	(29,568)
Cash flows from financing activities:
Net proceeds from subordinated notes offering	0	394,308	0
Common stock repurchased and restricted stock surrendered		(8,505)	(75,369)
Common stock dividends paid		(119,443)	$ (159,748)
Supplemental disclosures of cash flow information:
Fair value of assets acquired	4,090,143	4,144,900
Liabilities assumed	$ 139,612	$ 145,270