Consolidated Statement of Cash Flows - Unaudited - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 237,652	$ 204,994
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	26,555	37,490
Amortization of premiums and accretion of discount, net	11,824	5,770
Stock compensation costs	8,433	7,817
Deferred income tax (expense) benefit	(7,083)	224
Provision for credit losses	8,000	0
Net gains on sales of loans	(2,922)	(1,781)
Gains on sales of AFS debt securities	(1,278)	(192)
Loans held-for-sale:
Originations and purchases	(447)	(5,718)
Proceeds from sales and paydowns/payoffs of loans originally classified as held-for-sale	461	7,644
Proceeds from distributions received from equity method investees	3,227	2,505
Net change in accrued interest receivable and other assets	(81,628)	185,503
Net change in accrued expenses and other liabilities	83,042	(101,574)
Other net operating activities	49	20
Total adjustments	48,233	137,708
Net cash provided by operating activities	285,885	342,702
CASH FLOWS FROM INVESTING ACTIVITIES
Investments in qualified affordable housing partnerships, tax credit and other investments	(32,853)	(52,756)
Interest-bearing deposits with banks	(79,633)	67,793
Resale agreements:
Proceeds from paydowns and maturities	554,932	223,952
Purchases	(158,251)	(923,990)
AFS debt securities:
Proceeds from sales	103,945	46,397
Proceeds from repayments, maturities and redemptions	446,301	473,808
Purchases	(746,855)	(2,969,640)
HTM debt securities:
Proceeds from repayments, maturities and redemptions	15,448	0
Loans held-for-investment:
Proceeds from sales of loans originally classified as held-for-investment	135,517	147,115
Purchases	(225,065)	(311,030)
Other changes in loans held-for-investment, net	(1,697,590)	(1,047,557)
Proceeds from distributions received from equity method investees	4,348	2,832
Other net investing activities	(2,758)	(2,870)
Net cash used in investing activities	(1,682,514)	(4,345,946)
CASH FLOWS FROM FINANCING ACTIVITIES
Net increase in deposits	1,584,344	4,690,658
Net decrease in short-term borrowings	(31)	(21,143)
FHLB advances:
Proceeds	100	0
Repayment	(175,100)	0
Long-term debt and lease liabilities:
Repayment of long-term debt and lease liabilities	(229)	(315)
Common stock:
Stocks tendered for payment of withholding taxes	(18,597)	(14,983)
Cash dividends paid	(58,900)	(48,213)
Net cash provided by financing activities	1,331,587	4,606,004
Effect of exchange rate changes on cash and cash equivalents	807	(1,598)
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(64,235)	601,162
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	3,912,935	4,017,971
CASH AND CASH EQUIVALENTS, END OF PERIOD	3,848,700	4,619,133
Cash paid during the period for:
Interest	20,881	29,680
Income tax refund	581	0
Noncash investing and financing activities:
Securities transferred from AFS to HTM debt securities	3,010,003	0
Loans transferred from held-for-investment to held-for-sale	133,217	145,872
Loans transferred to other real estate owned (“OREO”) and other foreclosed assets	$ 0	$ 10,360