Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Gross amount of debt extinguished.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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BORROWED FUNDS - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Dec. 03, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Extinguishment of debt, amount	$ 750
Gains (losses) on extinguishment of debt	$ 3	$ 3	$ 0	$ 0
Long-term borrowed funds		9,886	4,642
Short-term borrowed funds		3,432	10,529
Federal Home Loan Bank Advances and Letters of Credit \| Secured Debt
Debt Instrument [Line Items]
Short-term borrowed funds		11,300	11,300
Federal Home Loan advances
Debt Instrument [Line Items]
Available borrowing capacity		4,100	3,500
Federal Reserve Bank advances
Debt Instrument [Line Items]
Available borrowing capacity		32,100
Citizens Financial Group, Inc.
Debt Instrument [Line Items]
Long-term borrowed funds		2,595
Citizens Financial Group, Inc. \| 4.300% fixed rate subordinated debt, due 2025 \| Subordinated Debt
Debt Instrument [Line Items]
Long-term borrowed funds		$ 750	$ 0
Interest rate		4.30%