Loans and Allowance for Loan Losses - Loans in Consumer Portfolio an Purchased credit-impaired loans (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Consumer portfolio loans
Nonaccrual	$ 465	$ 689
Consumer
Consumer portfolio loans
Loans covered by FDIC loss share agreements	8	11
Accrual	37,430	33,245
Nonaccrual	135	200
Total loans held for investment, before purchased credit-impaired loans	37,565	33,445
Consumer \| Residential mortgage
Consumer portfolio loans
Accrual	34,088	29,751
Nonaccrual	112	171
Total loans held for investment, before purchased credit-impaired loans	34,200	29,922
Consumer \| Home equity and other consumer loans
Consumer portfolio loans
Accrual	3,342	3,494
Nonaccrual	23	29
Total loans held for investment, before purchased credit-impaired loans	$ 3,365	$ 3,523

Financing receivable recorded investment accrual status.

No definition available.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes purchased credit impaired loans.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Details

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