FAIR VALUE MEASUREMENTS - Schedule of Assets and Liabilities Measured and Recorded at Fair Value (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Assets
Derivatives	$ 26	$ 22
Liabilities
Derivatives	49	61
Mutual funds
Assets
Fair Value of Investments	1,031	978
U.S. Government securities
Assets
Fair Value of Investments	104	105
Other securities
Assets
Fair Value of Investments	244	144
Level 1
Assets
Derivatives	0	0
Liabilities
Derivatives	0	0
Level 1 \| Mutual funds
Assets
Fair Value of Investments	1,031	978
Level 1 \| U.S. Government securities
Assets
Fair Value of Investments	0	0
Level 1 \| Other securities
Assets
Fair Value of Investments	113	28
Level 2
Assets
Derivatives	26	22
Liabilities
Derivatives	49	61
Level 2 \| Mutual funds
Assets
Fair Value of Investments	0	0
Level 2 \| U.S. Government securities
Assets
Fair Value of Investments	104	105
Level 2 \| Other securities
Assets
Fair Value of Investments	131	116
NAV \| Other commingled funds
Liabilities
Assets measured at NAV	$ 19	$ 18

Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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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 portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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