CONSOLIDATED STATEMENT 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	$ 1,161,161	$ 1,128,083	$ 872,981
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for (reversal of) credit losses	125,000	73,500	(35,000)
Depreciation and amortization	163,460	159,851	156,792
Accretion of discount and (amortization of premiums), net	10,723	56,703	67,415
Stock compensation costs	39,867	37,601	32,567
Deferred income tax (benefit) expense	(49,139)	(43,988)	4,762
Net gains on sales of loans	(3,634)	(6,411)	(8,909)
Net losses (gains) on AFS debt securities	6,862	(1,306)	(1,568)
Net gains on sales of other real estate owned ("OREO") and other foreclosed assets	(3,451)	(3,042)	(1,977)
Impairment on OREO and other foreclosed assets	0	6,861	5,151
Loans held-for-sale:
Originations and purchases	(116)	(447)	(11,155)
Proceeds from sales and paydowns/payoffs of loans originally classified as held-for-sale	0	461	12,552
Proceeds from distributions received from equity method investees	11,282	7,586	13,117
Net change in accrued interest receivable and other assets	(146,270)	187,512	124,496
Net change in accrued expenses and other liabilities	105,304	461,385	(63,360)
Other operating activities, net	3,860	1,673	558
Total adjustments	263,748	937,939	295,441
Net cash provided by operating activities	1,424,909	2,066,022	1,168,422
Net (increase) decrease in:
Investments in qualified affordable housing partnerships, tax credit and other investments	(228,550)	(167,303)	(189,836)
Interest-bearing deposits with banks	128,523	596,994	73,263
Resale agreements:
Proceeds from paydowns and maturities	219,917	1,951,388	982,694
Purchases	(212,725)	(390,077)	(1,876,197)
AFS debt securities:
Proceeds from sales	3,138	129,181	308,812
Proceeds from repayments, maturities and redemptions	1,470,819	896,726	1,766,184
Purchases	(1,549,846)	(1,070,608)	(6,779,655)
HTM debt securities:
Proceeds from repayments, maturities and redemptions	61,744	75,635	0
Purchases	0	(50,000)	0
Loans held-for-investment:
Proceeds from sales of loans originally classified as held-for-investment	711,862	602,725	606,410
Purchases	(600,930)	(657,620)	(1,045,456)
Other changes in loans held-for-investment, net	(4,166,572)	(6,516,182)	(2,877,438)
Proceeds from sales of OREO and other foreclosed assets	3,721	6,482	54,338
Purchase of bank-owned life insurance	0	(734)	(150,000)
Distributions received from equity method investees	23,774	18,221	14,440
Other investing activities, net	(112,036)	(7,720)	(4,763)
Net cash used in investing activities	(4,247,161)	(4,582,892)	(9,117,204)
CASH FLOWS FROM FINANCING ACTIVITIES
Net increase in deposits	144,468	2,709,427	8,464,285
Net increase (decrease) in short-term borrowings	4,500,000	6	(21,143)
FHLB advances:
Proceeds	6,000,000	4,950,200	400
Repayments	(6,000,000)	(5,200,200)	(405,400)
Repurchase agreements:
Repayment	(300,000)	0	0
Extinguishment cost	(3,872)	0	0
Long-term debt and lease liabilities:
Repayments of long-term debt and lease liabilities	(871)	(943)	(1,206)
Common stock:
Proceeds from issuance pursuant to various stock compensation plans and agreements	3,208	3,178	2,573
Stocks tendered for payment of withholding taxes	(23,751)	(19,087)	(15,702)
Repurchase of common stocks pursuant to the Stock Repurchase Program	(82,174)	(99,990)	0
Cash dividends paid	(274,554)	(228,381)	(188,762)
Net cash provided by financing activities	3,962,454	2,114,210	7,835,045
Effect of exchange rate changes on cash and cash equivalents	(7,002)	(28,491)	8,701
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1,133,200	(431,151)	(105,036)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3,481,784	3,912,935	4,017,971
CASH AND CASH EQUIVALENTS, END OF YEAR	4,614,984	3,481,784	3,912,935
Cash paid during the year for:
Interest	1,213,319	249,587	87,684
Income taxes, net	291,685	281,269	139,460
Noncash investing and financing activities:
Loans transferred from held-for-investment to held-for-sale	739,379	623,777	599,610
Securities transferred from AFS to HTM debt securities	0	3,010,003	0
Loans transferred to OREO	$ 11,141	$ 270	$ 49,485