XML 125 R160.htm IDEA: XBRL DOCUMENT v2.4.1.9
DERIVATIVES ACTIVITIES - Derivative Mark-to-Market (MTM) Receivables/Payables (Details) (USD $)
Dec. 31, 2014
Dec. 31, 2013
Derivative Mark-to-Market (MTM) Receivables/Payables    
Netting of cash collateral received $ (47,625,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset $ (34,893,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
Netting of cash collateral paid (47,769,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset (39,094,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
Cash collateral paid 0us-gaap_DerivativeCollateralRightToReclaimCash  
Non-cash collateral paid 0us-gaap_DerivativeCollateralRightToReclaimSecurities  
Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Cash collateral received, gross   138,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember
Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 886,237,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 795,239,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Cash collateral paid, net of amount used to offset derivative liabilities 6,523,000,000c_DerivativeCollateralRightToReclaimCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 6,073,000,000c_DerivativeCollateralRightToReclaimCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Less: Netting agreements to assets (777,178,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (713,598,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Netting of cash collateral received (47,625,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (34,893,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Total trading account derivatives, assets 67,957,000,000us-gaap_DerivativeAssets
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 52,821,000,000us-gaap_DerivativeAssets
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Cash collateral received (867,000,000)us-gaap_DerivativeCollateralObligationToReturnCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (365,000,000)us-gaap_DerivativeCollateralObligationToReturnCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Non-cash collateral received (10,043,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (7,478,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Total Net receivables 57,047,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 44,978,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Cash collateral paid, gross 54,292,000,000c_DerivativeCollateralRightToReclaimCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 45,167,000,000c_DerivativeCollateralRightToReclaimCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Does not meet applicable offsetting guidance, assets 11,000,000,000us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 16,000,000,000us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Trading accounts assets | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to assets   (392,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember
Less: Netting agreements to liabilities   (392,000,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember
Trading accounts assets | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to assets   (317,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember
Less: Netting agreements to liabilities   (317,000,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember
Trading accounts assets | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to assets   (5,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeTradedMember
Less: Netting agreements to liabilities   (5,000,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeTradedMember
Trading accounts liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 883,193,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 791,119,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Cash collateral received, net of amount used to offset derivative assets 9,846,000,000c_DerivativeCollateralObligationToReturnCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 8,827,000,000c_DerivativeCollateralObligationToReturnCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Less: Netting agreements to liabilities (777,178,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (713,598,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Netting of cash collateral paid (47,769,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (39,094,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Total derivative liabilities 68,092,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 47,254,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Cash collateral paid (11,000,000)us-gaap_DerivativeCollateralRightToReclaimCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (5,000,000)us-gaap_DerivativeCollateralRightToReclaimCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Non-cash collateral paid (6,264,000,000)us-gaap_DerivativeCollateralRightToReclaimSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (3,345,000,000)us-gaap_DerivativeCollateralRightToReclaimSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Total Net payables 61,817,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 43,904,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Cash collateral received, gross 57,471,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 43,720,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Does not meet applicable offsetting guidance, liabilities 10,000,000,000us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangement
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 16,000,000,000us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangement
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Trading accounts liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to assets (509,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember		  
Less: Netting agreements to liabilities (510,000,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember		  
Netting of cash collateral paid (46,000,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember		 (33,000,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember
Trading accounts liabilities | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to assets (263,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember		  
Less: Netting agreements to liabilities (264,000,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember		  
Netting of cash collateral paid (2,000,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember		 (6,000,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember
Trading accounts liabilities | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to assets (5,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeTradedMember		  
Less: Netting agreements to liabilities (3,000,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeTradedMember		  
Other assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 4,326,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 4,290,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Cash collateral paid, net of amount used to offset derivative liabilities 123,000,000c_DerivativeCollateralRightToReclaimCashNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 82,000,000c_DerivativeCollateralRightToReclaimCashNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Less: Netting agreements to assets 0us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 0us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Netting of cash collateral received (1,791,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 (2,951,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Total trading account derivatives, assets 2,658,000,000us-gaap_DerivativeAssets
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 1,421,000,000us-gaap_DerivativeAssets
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Cash collateral received 0us-gaap_DerivativeCollateralObligationToReturnCash
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 0us-gaap_DerivativeCollateralObligationToReturnCash
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Non-cash collateral received (1,293,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 (341,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Total Net receivables 1,365,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 1,080,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Other liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 1,784,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 1,729,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Cash collateral received, net of amount used to offset derivative assets 7,000,000c_DerivativeCollateralObligationToReturnCashNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 282,000,000c_DerivativeCollateralObligationToReturnCashNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Less: Netting agreements to liabilities 0us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 0us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Netting of cash collateral received (15,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		  
Netting of cash collateral paid (15,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 0us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Total derivative liabilities 1,776,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 2,011,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Cash collateral paid   0us-gaap_DerivativeCollateralRightToReclaimCash
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Non-cash collateral paid   0us-gaap_DerivativeCollateralRightToReclaimSecurities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Total Net payables 1,776,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 2,011,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Cash collateral received, gross 1,798,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 3,233,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 9,693,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 5,001,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Trading accounts liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 1,815,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 2,135,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Other assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 3,795,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 4,076,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Other liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 1,027,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 1,149,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 5,808,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 3,461,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts assets | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 1,508,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember		 956,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts assets | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 4,300,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember		 2,505,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 1,072,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 891,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 204,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember		 306,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 359,689,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts liabilities | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts liabilities | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other assets | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other assets | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other assets | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other liabilities | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Other liabilities | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Trading accounts assets | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Trading accounts assets | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Trading accounts liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Trading accounts liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Trading accounts liabilities | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Trading accounts liabilities | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Other assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Other assets | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Other assets | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Other assets | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Other liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Other liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Foreign exchange contracts | Other liabilities | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Trading accounts liabilities    
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Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Other assets    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Other assets | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Other liabilities    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Other liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Other liabilities | Cleared    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Purchased | Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Purchased | Trading accounts liabilities    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Sold | Trading accounts assets    
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