Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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RELATED PARTY TRANSACTIONS AND SIGNIFICANT TRANSACTIONS WITH RBS - Narrative (Details) - USD ($)				3 Months Ended		6 Months Ended
	Jul. 28, 2016	Mar. 07, 2016	Dec. 03, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Related Party Transaction [Line Items]
Repurchase of long-term borrowed funds						$ 3,631,000,000	$ 6,000,000
Gain on extinguishment of debt			$ 3,000,000
RBSG
Related Party Transaction [Line Items]
Repurchase of long-term borrowed funds		$ 125,000,000	$ 750,000,000
Payments of ordinary common stock dividends				$ 0	$ 21,000,000	0	$ 60,000,000
Executive Officers, Family Members, and Their Businesses
Related Party Transaction [Line Items]
Related party loans				$ 141,000,000		$ 141,000,000		$ 136,000,000
Subsequent Event \| RBSG
Related Party Transaction [Line Items]
Repurchase of long-term borrowed funds	$ 500,000,000