Gross Realized Gains and Losses on Sales and OTTI on Securities Available for Sale (parenthetical) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Gain (Loss) on Investments [Line Items]
Executed Equity Forward Agreements, Losses Recognized In Securities Gains	$ 305

Losses recognized in securities gains related to the executed equity forward agreements of common shares of The Coca-Cola Company.

No definition available.

Name:	sti_ExecutedEquityForwardAgreementsLossesRecognizedInSecuritiesGains
Namespace Prefix:	sti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration