Loans and Allowance for Loan Losses - Loans in Consumer Portfolio an Purchased credit-impaired loans (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Consumer portfolio loans
Nonaccrual	$ 634	$ 421
Consumer
Consumer portfolio loans
Loans covered by FDIC loss share agreements	5	6
Accrual	43,823	43,226
Nonaccrual	144	140
Total loans held for investment, before purchased credit-impaired loans	43,967	43,366
Consumer \| Residential Mortgage
Consumer portfolio loans
Total loans held for investment, before purchased credit-impaired loans	38,436	38,435
Consumer \| Home equity and other consumer loans
Consumer portfolio loans
Total loans held for investment, before purchased credit-impaired loans	5,531	4,931
Residential Mortgage \| Consumer Loans Portfolio Segment [Member]
Consumer portfolio loans
Accrual	38,312	38,314
Nonaccrual	124	121
Home equity and other consumer loans \| Consumer Loans Portfolio Segment [Member]
Consumer portfolio loans
Accrual	5,511	4,912
Nonaccrual	$ 20	$ 19

Financing receivable recorded investment accrual status.

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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

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+ 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
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&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=82891408&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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