The amount of the acquisition price paid in a leveraged buyout in which the entity served as lender and advisor.

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Represents the aggregate original purchase amount of collateralized debt obligations and mortgage backed securities underwritten by the entity, which are covered by tolling agreements with investors threatening litigation.

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Loss Contingency, Number of Mortgage-Backed Securities Trusts Dismissed from Claims

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Represents the collection period of interchange fees.

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Amount awarded to other party in judgment or settlement of litigation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of damages awarded to the plaintiff in the legal matter.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Number of plaintiffs that have filed claims pertaining to a loss contingency.

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The difference between the maximum amount of estimated loss and the amount recorded as of the balance sheet date.

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CONTINGENCIES (Details) $ in Thousands, € in Billions							12 Months Ended
CONTINGENCIES (Details) $ in Thousands, € in Billions	Dec. 20, 2018 USD ($)	Dec. 19, 2018 USD ($)	Dec. 05, 2018 USD ($)	Nov. 07, 2018 USD ($)	Aug. 16, 2018 USD ($)	May 22, 2018 USD ($)	Dec. 31, 2016 USD ($) plaintiff	Dec. 31, 2015 EUR (€)	Dec. 31, 2014 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2015 trust
Contingencies
Possible unaccrued loss											$ 1,000,000
Mortgage-backed securities trustee actions
Contingencies
Number of MBS trusts dismissed from claims \| trust												24
Tribune Company bankruptcy
Contingencies
Business acquisition price LBO											11,000,000
In Re Citigroup Inc. Securities Litigation \| Mortgage-backed securities trustee actions
Contingencies
Aggregate original purchase amount of the purchases covered by tolling agreements											$ 500,000
Depository Receipt Matters
Contingencies
Settlement amount awarded to other party				$ 38,700
LIBOR-based Financial Instruments Antitrust Litigation
Contingencies
Settlement amount awarded to other party	$ 23,000		$ 7,025
EURIBOR Manipulation
Contingencies
Settlement amount awarded to other party		$ 182,500
Frontpoint Asian Event Driven Fund v. Citibank
Contingencies
Settlement amount awarded to other party						$ 9,990
Interchange Fees Litigation
Contingencies
Settlement amount awarded to other party									$ 6,050,000
Period of collecting interchange fees									8 months
Oceanografia Fraud and Related Matters
Contingencies
Settlement amount awarded to other party					$ 4,750
Number of plaintiffs \| plaintiff							39
Loss contingency damages sought							$ 1,100,000
Parmalat
Contingencies
Damages awarded									$ 431,000	$ 431,000
Parmalat \| Milan Court of Appeal \| Citibank, N.A.
Contingencies
Loss contingency damages sought \| €								€ 1.8