Loans And The Allowance For Credit Losses (Analysis Of The Allowance For Credit Losses By Portfolio Segment) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	$ 1,613	$ 1,617	$ 1,613	$ 1,576
Provision for loan losses	112	105	235	267
Loan Losses:
Charge-offs	(133)	(123)	(278)	(264)
Recoveries	20	22	42	42
Net loan (losses) recoveries	(113)	(101)	(236)	(222)
Allowance for loan losses, end of period	1,612	1,621	1,612	1,621
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	117	114	116	124
Provision (credit) for unfunded credit losses	14	(3)	15	(13)
Reserve for unfunded credit commitments, end of year	131	111	131	111
Allowance for credit losses	1,743	1,732	1,743	1,732
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	745	756	743	722
Provision for loan losses	62	31	111	119
Loan Losses:
Charge-offs	(70)	(61)	(129)	(123)
Recoveries	10	10	22	18
Net loan (losses) recoveries	(60)	(51)	(107)	(105)
Allowance for loan losses, end of period	747	736	747	736
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	91	87	91	92
Provision (credit) for unfunded credit losses	8	(2)	8	(7)
Reserve for unfunded credit commitments, end of year	99	85	99	85
Allowance for credit losses	846	821	846	821
Investor Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	236	211	240	192
Provision for loan losses	0	21	18	44
Loan Losses:
Charge-offs	(2)	0	(24)	(5)
Recoveries	0	1	0	2
Net loan (losses) recoveries	(2)	1	(24)	(3)
Allowance for loan losses, end of period	234	233	234	233
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	8	10	7	13
Provision (credit) for unfunded credit losses	5	(2)	6	(5)
Reserve for unfunded credit commitments, end of year	13	8	13	8
Allowance for credit losses	247	241	247	241
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	632	650	630	662
Provision for loan losses	50	53	106	104
Loan Losses:
Charge-offs	(61)	(62)	(125)	(136)
Recoveries	10	11	20	22
Net loan (losses) recoveries	(51)	(51)	(105)	(114)
Allowance for loan losses, end of period	631	652	631	652
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	18	17	18	19
Provision (credit) for unfunded credit losses	1	1	1	(1)
Reserve for unfunded credit commitments, end of year	19	18	19	18
Allowance for credit losses	$ 650	$ 670	$ 650	$ 670

Financing Receivable, Allowance for Credit Loss, Including Unfunded Credit Commitments Excluding Accrued Interest

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Provision for unfunded credit commitments

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Reserve For Unfunded Credit Commitments

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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