RELATED PARTY TRANSACTIONS AND SIGNIFICANT TRANSACTIONS WITH RBS - Schedule of Related Party Transactions, Recorded Income (Expense) (Details) - RBSG - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Interest rate swaps
Schedule of Related Party Transactions, Recorded Income (Expense) [Line Items]
Derivative expense	$ (105)	$ (209)	$ (32)
Foreign exchange contracts
Schedule of Related Party Transactions, Recorded Income (Expense) [Line Items]
Foreign exchange and trade finance revenue	$ 19	$ 58	$ (15)

[Line Items] for Tabular disclosure of the income (expense) recorded in relation to swap and cap agreements and foreign exchange contracts with related parties.

No definition available.

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