Borrowings - Stated Maturities and Maturities to Call Dates (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
2014	$ 14,500
2015	14,400
2016	12,500
2017	12,600
2018	11,900
2019 and after	69,600
Total, long-term debt	136,648	152,401
Stated Maturity [Member]
Debt Instrument [Line Items]
2014	14,408
2015	14,373
2016	12,430
2017	12,524
2018	11,819
2019 and after	69,054
Long term debt maturities total	134,608
Hedge accounting adjustments	2,040
Total, long-term debt	136,648
Stated Maturity [Member] \| Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
2015	1,506
2016	2,284
2017	1,829
2018	2,796
2019 and after	7,641
Long term debt maturities total	16,056
Hedge accounting adjustments	727
Total, long-term debt	16,783
Stated Maturity [Member] \| Brokered Deposits [Member]
Debt Instrument [Line Items]
2015	1,195
2016	648
2017	538
2018	426
Long term debt maturities total	2,807
Total, long-term debt	2,807
Stated Maturity [Member] \| Secured Borrowings [Member]
Debt Instrument [Line Items]
2014	14,408
2015	11,672
2016	9,498
2017	10,157
2018	8,597
2019 and after	61,413
Long term debt maturities total	115,745
Hedge accounting adjustments	1,313
Total, long-term debt	117,058
Maturity to Call Date [Member]
Debt Instrument [Line Items]
2014	16,019
2015	14,462
2016	12,429
2017	12,502
2018	11,570
2019 and after	67,626
Long term debt maturities total	134,608
Hedge accounting adjustments	2,040
Total, long-term debt	136,648
Maturity to Call Date [Member] \| Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
2014	1,611
2015	1,595
2016	2,283
2017	1,807
2018	2,547
2019 and after	6,213
Long term debt maturities total	16,056
Hedge accounting adjustments	727
Total, long-term debt	16,783
Maturity to Call Date [Member] \| Brokered Deposits [Member]
Debt Instrument [Line Items]
2015	1,195
2016	648
2017	538
2018	426
Long term debt maturities total	2,807
Total, long-term debt	2,807
Maturity to Call Date [Member] \| Secured Borrowings [Member]
Debt Instrument [Line Items]
2014	14,408
2015	11,672
2016	9,498
2017	10,157
2018	8,597
2019 and after	61,413
Long term debt maturities total	115,745
Hedge accounting adjustments	1,313
Total, long-term debt	$ 117,058

ASC 815 - Derivatives and Hedging fair value adjustments.

No definition available.

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- Definition

Total amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year through after the fifth fiscal year following the latest fiscal year.

+ References

No definition available.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB

-Name Accounting Standards Codification

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

+ References

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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