XML 79 R108.htm IDEA: XBRL DOCUMENT v2.4.1.9
Carrying Amounts and Fair Values of the Company's Financial Instruments (Detail) (USD $)
In Millions, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Dec. 31, 2014
Financial assets    
Trading assets $ 6,595us-gaap_TradingSecurities [1] $ 6,202us-gaap_TradingSecurities [1]
Available-for-sale Securities 26,761us-gaap_AvailableForSaleSecurities [2] 26,770us-gaap_AvailableForSaleSecurities [2]
Loans Held-for-sale, Fair Value Disclosure 2,077us-gaap_LoansHeldForSaleFairValueDisclosure 1,892us-gaap_LoansHeldForSaleFairValueDisclosure
Financial liabilities    
Long-term Debt, Fair Value 1,281us-gaap_LongTermDebtFairValue 1,283us-gaap_LongTermDebtFairValue
Trading liabilities 1,459us-gaap_TradingLiabilitiesFairValueDisclosure 1,227us-gaap_TradingLiabilitiesFairValueDisclosure
Estimate of Fair Value, Fair Value Disclosure [Member]    
Financial assets    
Cash and cash equivalents 7,738us-gaap_CashAndCashEquivalentsFairValueDisclosure
/ us-gaap_FairValueByMeasurementBasisAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 8,229us-gaap_CashAndCashEquivalentsFairValueDisclosure
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Trading assets 6,595us-gaap_TradingSecurities
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 6,202us-gaap_TradingSecurities
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Available-for-sale Securities 26,761us-gaap_AvailableForSaleSecurities
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Loans Held-for-sale, Fair Value Disclosure 3,423us-gaap_LoansHeldForSaleFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Loans Net Fair Value Disclosure 126,722sti_LoansNetFairValueDisclosure
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Financial liabilities    
Consumer And Commercial Deposits, Fair Value Disclosure 144,414sti_ConsumerAndCommercialDepositsFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 140,562sti_ConsumerAndCommercialDepositsFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Short Term Borrowings Fair Value Disclosure 4,582sti_ShortTermBorrowingsFairValueDisclosure
/ us-gaap_FairValueByMeasurementBasisAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 9,186sti_ShortTermBorrowingsFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Long-term Debt, Fair Value 13,070us-gaap_LongTermDebtFairValue
/ us-gaap_FairValueByMeasurementBasisAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 13,056us-gaap_LongTermDebtFairValue
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Trading liabilities 1,459us-gaap_TradingLiabilitiesFairValueDisclosure
/ us-gaap_FairValueByMeasurementBasisAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 1,227us-gaap_TradingLiabilitiesFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 1 [Member]    
Financial assets    
Cash and cash equivalents 7,738us-gaap_CashAndCashEquivalentsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 8,229us-gaap_CashAndCashEquivalentsFairValueDisclosure
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= us-gaap_FairValueInputsLevel1Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Trading assets 1,112us-gaap_TradingSecurities
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Available-for-sale Securities 2,346us-gaap_AvailableForSaleSecurities
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= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementBasisAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 2,059us-gaap_AvailableForSaleSecurities
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= us-gaap_FairValueInputsLevel1Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Loans Held-for-sale, Fair Value Disclosure 0us-gaap_LoansHeldForSaleFairValueDisclosure
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= us-gaap_FairValueInputsLevel1Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 0us-gaap_LoansHeldForSaleFairValueDisclosure
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= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementBasisAxis
= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Loans Net Fair Value Disclosure 0sti_LoansNetFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Financial liabilities    
Consumer And Commercial Deposits, Fair Value Disclosure 0sti_ConsumerAndCommercialDepositsFairValueDisclosure
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= us-gaap_FairValueInputsLevel1Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 0sti_ConsumerAndCommercialDepositsFairValueDisclosure
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Short Term Borrowings Fair Value Disclosure 0sti_ShortTermBorrowingsFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Long-term Debt, Fair Value 0us-gaap_LongTermDebtFairValue
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= us-gaap_FairValueInputsLevel1Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Trading liabilities 1,039us-gaap_TradingLiabilitiesFairValueDisclosure
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= us-gaap_FairValueInputsLevel1Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 929us-gaap_TradingLiabilitiesFairValueDisclosure
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Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 2 [Member]    
Financial assets    
Cash and cash equivalents 0us-gaap_CashAndCashEquivalentsFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 0us-gaap_CashAndCashEquivalentsFairValueDisclosure
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Trading assets 5,438us-gaap_TradingSecurities
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 5,177us-gaap_TradingSecurities
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Available-for-sale Securities 23,648us-gaap_AvailableForSaleSecurities
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= us-gaap_FairValueInputsLevel2Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 23,765us-gaap_AvailableForSaleSecurities
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Loans Held-for-sale, Fair Value Disclosure 2,182us-gaap_LoansHeldForSaleFairValueDisclosure
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= us-gaap_FairValueInputsLevel2Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 2,063us-gaap_LoansHeldForSaleFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Loans Net Fair Value Disclosure 543sti_LoansNetFairValueDisclosure
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= us-gaap_FairValueInputsLevel2Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Financial liabilities    
Consumer And Commercial Deposits, Fair Value Disclosure 144,414sti_ConsumerAndCommercialDepositsFairValueDisclosure
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Short Term Borrowings Fair Value Disclosure 4,582sti_ShortTermBorrowingsFairValueDisclosure
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Long-term Debt, Fair Value 12,424us-gaap_LongTermDebtFairValue
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= us-gaap_FairValueInputsLevel2Member
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 12,398us-gaap_LongTermDebtFairValue
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= us-gaap_FairValueInputsLevel2Member
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Trading liabilities 412us-gaap_TradingLiabilitiesFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember		 293us-gaap_TradingLiabilitiesFairValueDisclosure
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Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 3 [Member]    
Financial assets    
Cash and cash equivalents 0us-gaap_CashAndCashEquivalentsFairValueDisclosure
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Trading assets 45us-gaap_TradingSecurities
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Available-for-sale Securities 767us-gaap_AvailableForSaleSecurities
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Loans Held-for-sale, Fair Value Disclosure 1,241us-gaap_LoansHeldForSaleFairValueDisclosure
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Loans Net Fair Value Disclosure 126,179sti_LoansNetFairValueDisclosure
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= us-gaap_EstimateOfFairValueFairValueDisclosureMember
Financial liabilities    
Consumer And Commercial Deposits, Fair Value Disclosure 0sti_ConsumerAndCommercialDepositsFairValueDisclosure
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Short Term Borrowings Fair Value Disclosure 0sti_ShortTermBorrowingsFairValueDisclosure
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Long-term Debt, Fair Value 646us-gaap_LongTermDebtFairValue
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Trading liabilities 8us-gaap_TradingLiabilitiesFairValueDisclosure
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Carrying (Reported) Amount, Fair Value Disclosure    
Financial assets    
Cash and cash equivalents 7,738us-gaap_CashAndCashEquivalentsFairValueDisclosure
/ us-gaap_FairValueByMeasurementBasisAxis
= us-gaap_CarryingReportedAmountFairValueDisclosureMember		 8,229us-gaap_CashAndCashEquivalentsFairValueDisclosure
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Trading assets 6,595us-gaap_TradingSecurities
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= us-gaap_CarryingReportedAmountFairValueDisclosureMember		 6,202us-gaap_TradingSecurities
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Available-for-sale Securities 26,761us-gaap_AvailableForSaleSecurities
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Loans Held-for-sale, Fair Value Disclosure 3,404us-gaap_LoansHeldForSaleFairValueDisclosure
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Loans Net Fair Value Disclosure 130,487sti_LoansNetFairValueDisclosure
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Financial liabilities    
Consumer And Commercial Deposits, Fair Value Disclosure 144,423sti_ConsumerAndCommercialDepositsFairValueDisclosure
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= us-gaap_CarryingReportedAmountFairValueDisclosureMember
Short Term Borrowings Fair Value Disclosure 4,582sti_ShortTermBorrowingsFairValueDisclosure
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Long-term Debt, Fair Value 13,012us-gaap_LongTermDebtFairValue
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= us-gaap_CarryingReportedAmountFairValueDisclosureMember		 13,022us-gaap_LongTermDebtFairValue
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Trading liabilities 1,459us-gaap_TradingLiabilitiesFairValueDisclosure
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Affordable Housing [Member]    
Gains (Losses) on Sales of Investment Real Estate $ 18us-gaap_GainsLossesOnSalesOfInvestmentRealEstate
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= sti_AffordableHousingMember		  
[1] Includes trading securities pledged as collateral where counterparties have the right to sell or repledge the collateral of $1,207 million and $1,316 million at March 31, 2015 and December 31, 2014, respectively
[2] Includes securities AFS pledged as collateral where counterparties have the right to sell or repledge the collateral of $0 million and $369 million at March 31, 2015 and December 31, 2014, respectively.