XML 137 R120.htm IDEA: XBRL DOCUMENT v2.4.1.9
DERIVATIVES ACTIVITIES - Derivative Mark-to-Market (MTM) Receivables/Payables (Details) (USD $)
Mar. 31, 2015
Dec. 31, 2014
Derivative Mark-to-Market (MTM) Receivables/Payables    
Netting of cash collateral received $ (53,848,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset $ (47,625,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
Netting of cash collateral paid (51,292,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset (47,769,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Cash collateral received, gross 2,206,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember		 138,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember
Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 897,772,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 886,237,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Cash collateral paid, net of amount used to offset derivative liabilities 7,270,000,000c_DerivativeCollateralRightToReclaimCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 6,523,000,000c_DerivativeCollateralRightToReclaimCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Less: Netting agreements to assets (779,613,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (777,178,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Netting of cash collateral received (53,848,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (47,625,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Total trading account derivatives, assets 71,581,000,000us-gaap_DerivativeAssets
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 67,957,000,000us-gaap_DerivativeAssets
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Cash collateral received (411,000,000)us-gaap_DerivativeCollateralObligationToReturnCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (867,000,000)us-gaap_DerivativeCollateralObligationToReturnCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Non-cash collateral received (10,091,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 (10,043,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Total Net receivables 61,079,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 57,047,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Cash collateral paid, gross 58,562,000,000c_DerivativeCollateralRightToReclaimCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 54,292,000,000c_DerivativeCollateralRightToReclaimCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
Does not meet applicable offsetting guidance, assets 11,000,000,000us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember		 11,000,000,000us-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 (521,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember		 (510,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_OverTheCounterMember
Less: Netting agreements to liabilities   (510,000,000,000)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 (252,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember		 (264,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember
Less: Netting agreements to liabilities   (264,000,000,000)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 (7,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeTradedMember		 (3,000,000,000)us-gaap_DerivativeAssetFairValueGrossLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeTradedMember
Less: Netting agreements to liabilities   (3,000,000,000)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 897,702,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 883,193,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Cash collateral received, net of amount used to offset derivative assets 10,398,000,000c_DerivativeCollateralObligationToReturnCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 9,846,000,000c_DerivativeCollateralObligationToReturnCashNet
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Less: Netting agreements to liabilities (779,613,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (777,178,000,000)us-gaap_DerivativeLiabilityFairValueGrossAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Netting of cash collateral paid (51,292,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (47,769,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Total derivative liabilities 77,195,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 68,092,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Cash collateral paid (7,000,000)us-gaap_DerivativeCollateralRightToReclaimCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (11,000,000)us-gaap_DerivativeCollateralRightToReclaimCash
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Non-cash collateral paid (8,156,000,000)us-gaap_DerivativeCollateralRightToReclaimSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 (6,264,000,000)us-gaap_DerivativeCollateralRightToReclaimSecurities
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Total Net payables 69,032,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 61,817,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Cash collateral received, gross 64,246,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 57,471,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Does not meet applicable offsetting guidance, liabilities 10,000,000,000us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangement
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember		 10,000,000,000us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangement
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
Trading accounts liabilities | Over-the-counter    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to liabilities (521,000,000,000)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
Trading accounts liabilities | Cleared    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to liabilities (252,000,000,000)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
Trading accounts liabilities | Exchange traded    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Less: Netting agreements to liabilities (7,000,000,000)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 4,496,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 4,326,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Cash collateral paid, net of amount used to offset derivative liabilities 29,000,000c_DerivativeCollateralRightToReclaimCashNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 123,000,000c_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 (2,150,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 (1,791,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Total trading account derivatives, assets 2,375,000,000us-gaap_DerivativeAssets
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 2,658,000,000us-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 (580,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 (1,293,000,000)us-gaap_DerivativeCollateralObligationToReturnSecurities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Total Net receivables 1,795,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember		 1,365,000,000us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
Other liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 1,968,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 1,784,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Cash collateral received, net of amount used to offset derivative assets 56,000,000c_DerivativeCollateralObligationToReturnCashNet
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 7,000,000c_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 (2,150,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 (15,000,000)us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Netting of cash collateral paid 0us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 (15,000,000)us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Total derivative liabilities 2,024,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 1,776,000,000us-gaap_DerivativeLiabilities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Cash collateral paid 0us-gaap_DerivativeCollateralRightToReclaimCash
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 0us-gaap_DerivativeCollateralRightToReclaimCash
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Non-cash collateral paid 0us-gaap_DerivativeCollateralRightToReclaimSecurities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 0us-gaap_DerivativeCollateralRightToReclaimSecurities
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Total Net payables 2,024,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember		 1,776,000,000us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Cash collateral received, gross   1,798,000,000c_DerivativeCollateralObligationToReturnCashGross
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative receivables 10,995,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 9,693,000,000us-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 2,296,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 1,815,000,000us-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 3,745,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherAssetsMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 3,795,000,000us-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 1,132,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= us-gaap_OtherLiabilitiesMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 1,027,000,000us-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 6,858,000,000us-gaap_DerivativeFairValueOfDerivativeAsset
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsAssetsMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 5,808,000,000us-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 2,000,000,000us-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		 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
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 4,858,000,000us-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		 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
Derivative instruments designated as ASC 815 (SFAS 133) hedges | Interest rate contracts | Trading accounts liabilities    
Derivative Mark-to-Market (MTM) Receivables/Payables    
Derivative payables 1,352,000,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_BalanceSheetLocationAxis
= c_TradingAccountsLiabilitiesMember
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateContractMember
/ us-gaap_HedgingDesignationAxis
= us-gaap_DesignatedAsHedgingInstrumentMember		 1,072,000,000us-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 1,282,000,000us-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		 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
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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 | Interest rate contracts | Other liabilities    
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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    
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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 instruments not designated as ASC 815 (SFAS 133) hedges | Equity contracts | Trading accounts assets    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Equity contracts | Trading accounts 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 | Equity 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 | Equity 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 | Equity 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 | Credit derivatives | Trading accounts liabilities | Cleared    
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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 assets | Cleared    
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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    
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 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    
Derivative Mark-to-Market (MTM) Receivables/Payables    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Sold | Trading accounts assets    
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Derivative instruments not designated as ASC 815 (SFAS 133) hedges | Credit derivatives | Sold | Trading accounts liabilities    
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