Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities
Income after income tax (benefit) expense	$ 137,351	$ 192,470
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision for credit losses	245,333	50,879
Share-based compensation expense	26,447	17,762
Depreciation and amortization	320,950	207,954
Provision (benefit) for deferred income taxes	(132,148)	(27,732)
Net gains on sales of assets	(97,068)	(46,966)
Proceeds from sales of loans and leases held-for-sale	1,271,793	512,051
Originations of loans and leases held-for-sale, net of repayments	(1,540,397)	(548,371)
Impairment of loan servicing rights	17,248	4,520
Net change in other assets	(422,496)	(188,081)
Net change in other liabilities	(165,881)	16,229
Other, net	(42,154)	(34,793)
Net cash provided by (used in) operating activities	(381,022)	155,922
Cash flows from investing activities
Proceeds from sales of investment securities available-for-sale	50,797	1,993,274
Proceeds from maturities of and principal collected on investment securities available-for-sale	1,646,241	398,989
Purchases of investment securities available-for-sale	(2,074,989)	(1,424,344)
Proceeds from maturities of and principal collected on investment securities held-to-maturity	22,643	11,945
Purchases of investment securities held-to-maturity	(27,428)	(4,029)
Redemption of Federal Home Loan Bank stock	344,014	162,011
Purchases of Federal Home Loan Bank stock	(202,000)	(142,000)
Proceeds from sales of loans and leases	530,734	566,880
Loan and lease originations and purchases, net of principal collected	(433,410)	(674,459)
Proceeds from sales of other assets	60,018	82,970
Purchases of premises and equipment and lease equipment	(75,885)	(108,404)
Net cash acquired (paid) in business combination	0	975,014
Other, net	23,456	(6,743)
Net cash provided by (used in) investing activities	(135,809)	1,831,104
Cash flows from financing activities
Net change in deposits	4,773,178	(15,296)
Net change in short-term borrowings	(2,013,623)	(17,292)
Proceeds from long-term borrowings	4,956,373	2,799,986
Payments on long-term borrowings	(6,445,567)	(3,838,454)
Payments on liabilities related to acquisition and portfolio purchase	0	(1,000)
Repurchases of common stock	(33,098)	(58,804)
Dividends paid on preferred stock	(7,481)	(7,481)
Dividends paid on common stock	(160,980)	(102,368)
Exercise of stock options	(110)	0
Payments related to tax-withholding upon conversion of share-based awards	(4,104)	(5,813)
Net investment by (distribution to) non-controlling interest	(4,874)	(4,547)
Net cash provided by (used in) financing activities	1,059,714	(1,251,069)
Net change in cash and due from banks	542,883	735,957
Cash and cash equivalents at beginning of period	1,228,371	587,057
Cash and cash equivalents at end of period	1,771,254	1,323,014
Cash paid (received) for:
Interest on deposits and borrowings	195,619	192,793
Income taxes, net	130,144	10,367
Noncash activities:
Transfer of loans and leases to other assets	38,938	73,314
Transfer of loans and leases from held-for-investment to held for sale, net	$ 426,063	$ 1,837,445