DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Notional Amounts and Gross Fair Values (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Document Period End Date	Jun. 30, 2019
Notional amount	$ 8,202.0	$ 6,942.0
Derivative asset, not offset against collateral	1.0	2.0
Derivative liability, not offset against collateral	25.0	13.0
Derivative asset, not subject to master netting arrangement	148.0	41.0
Derivative liability, not subject to master netting arrangement	2.0	26.0
Fair value, asset	149.0	43.0
Fair value, liability	27.0	39.0
Interest rate contracts - designated [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, not offset against collateral	1.0	0.0
Derivative liability, not offset against collateral	1.0	3.0
Interest rate swaps - not designated [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, not offset against collateral	0.0	2.0
Derivative liability, not offset against collateral	24.0	10.0
Derivative asset, not subject to master netting arrangement	145.0	40.0
Derivative liability, not subject to master netting arrangement	1.0	26.0
Equity contracts - not designated [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, not offset against collateral	0.0	0.0
Derivative liability, not offset against collateral	0.0	0.0
Derivative asset, not subject to master netting arrangement	0.0	0.0
Derivative liability, not subject to master netting arrangement	0.0	0.0
Interest rate lock commitments – not designated [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, not subject to master netting arrangement	3.0	1.0
Derivative liability, not subject to master netting arrangement	0.0	0.0
Forward delivery commitments – not designated [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, not subject to master netting arrangement	0.0	0.0
Derivative liability, not subject to master netting arrangement	1.0	0.0
Credit risk contracts - not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	165.2
Derivative asset, not subject to master netting arrangement	0.0	0.0
Derivative liability, not subject to master netting arrangement	0.0	0.0
Subject to Master Netting Arrangements [Member]
Derivatives, Fair Value [Line Items]
Notional amount	4,506.0	3,896.0
Subject to Master Netting Arrangements [Member] \| Interest rate contracts - designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	1,355.0	1,155.0
Subject to Master Netting Arrangements [Member] \| Interest rate swaps - not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	3,151.0	2,740.0
Subject to Master Netting Arrangements [Member] \| Equity contracts - not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	0.0	1.0
Not Subject to Master Netting Arrangements [Member]
Derivatives, Fair Value [Line Items]
Notional amount	3,696.0	3,046.0
Not Subject to Master Netting Arrangements [Member] \| Interest rate swaps - not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	3,151.0	2,740.0
Not Subject to Master Netting Arrangements [Member] \| Equity contracts - not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	0.0	1.0
Not Subject to Master Netting Arrangements [Member] \| Interest rate lock commitments – not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	130.0	47.0
Not Subject to Master Netting Arrangements [Member] \| Forward delivery commitments – not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	185.0	55.0
Not Subject to Master Netting Arrangements [Member] \| Credit risk contracts - not designated [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 230.0	$ 203.0

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

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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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