Fair Value Option Elected, Difference Between the Aggregate Fair Value and the Aggregate Unpaid Principal Balance (Detail) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
LHFS	$ 1,925	$ 3,168
Brokered deposits	1,140	1,213
Aggregate Fair Value Under Fair Value Option
Trading loans	1,581	1,353
LHFS	1,917	3,160
LHFI	419	462
Brokered deposits	1,140	1,213
Long-term debt	2,022	2,837
Aggregate Fair Value Under Fair Value Option \| Loans Held-for-Sale
Past due loans of 90 days or more	7	2
Nonaccrual loans	1	6
Aggregate Fair Value Under Fair Value Option \| Loans Held-for-Investment
Past due loans of 90 days or more	3	2
Nonaccrual loans	27	28
Aggregate Unpaid Principal Balance Under Fair Value Option
Trading loans	1,558	1,320
LHFS	1,886	3,155
LHFI	470	517
Brokered deposits	1,107	1,188
Long-term debt	1,901	2,753
Aggregate Unpaid Principal Balance Under Fair Value Option \| Loans Held-for-Sale
Past due loans of 90 days or more	7	2
Nonaccrual loans	8	25
Aggregate Unpaid Principal Balance Under Fair Value Option \| Loans Held-for-Investment
Past due loans of 90 days or more	5	4
Nonaccrual loans	48	54
Fair Value Over/(Under) Unpaid Principal
Trading loans	23	33
LHFS	31	5
LHFI	(51)	(55)
Brokered deposits	33	25
Long-term debt	121	84
Fair Value Over/(Under) Unpaid Principal \| Loans Held-for-Sale
Nonaccrual loans	(7)	(19)
Fair Value Over/(Under) Unpaid Principal \| Loans Held-for-Investment
Past due loans of 90 days or more	(2)	(2)
Nonaccrual loans	$ (21)	$ (26)

Interest-bearing Deposit Liabilities, Domestic, Measured at Fair Value.

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Namespace Prefix:	sti
Data Type:	xbrli:monetaryItemType
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- Definition

Loans, Held for Investment, Fair Value Disclosure

+ Details

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Namespace Prefix:	sti
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Balance Type:	debit
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- Definition

Long-term Debt, at Fair Value

+ Details

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Namespace Prefix:	sti
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph e(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph e(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents loans held-for-sale as presented on the statement of financial position which may include mortgage loans held-for-sale, finance receivables held-for-sale, or any other loans classified as held-for-sale which are due the Company as of the balance sheet date.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents marketable and other securities categorized as trading securities as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 4
-Article 9

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 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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