Loans and Allowance for Loan Losses - Loans in Consumer Portfolio Segment and Purchased Credit Impaired Loans Segment (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Consumer portfolio loans
Nonaccrual	$ 552	$ 375
Total loans held for investment, before purchased credit-impaired loans	77,263	76,279
Consumer
Consumer portfolio loans
Accrual	30,518	32,019
Nonaccrual	225	271
Total loans held for investment, before purchased credit-impaired loans	30,743	32,290
Loans not covered	18	28
Consumer portfolio
Consumer portfolio loans
Accrual	30,370	31,823
Nonaccrual	225	271
Total loans held for investment, before purchased credit-impaired loans	30,595	32,094
Consumer portfolio \| Residential mortgage
Consumer portfolio loans
Accrual	27,154	28,746
Nonaccrual	190	231
Total loans held for investment, before purchased credit-impaired loans	27,344	28,977
Consumer portfolio \| Home equity and other consumer loans
Consumer portfolio loans
Accrual	3,216	3,077
Nonaccrual	35	40
Total loans held for investment, before purchased credit-impaired loans	3,251	3,117
Purchased credit-impaired loans
Consumer portfolio loans
Nonaccrual	6	9
Purchased credit-impaired loans \| Consumer
Consumer portfolio loans
Accrual	148	196
Nonaccrual	0	0
Total loans held for investment, before purchased credit-impaired loans	$ 148	$ 196

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.

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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 (d)
-URI http://asc.fasb.org/extlink&oid=49124121&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=28367877&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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