RETIREMENT AND POSTRETIREMENT BENEFIT PLANS - FAIR VALUE OF PENSION PLAN ASSETS (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 1,639	$ 338	$ 403
U.S. government securities
Defined Benefit Plan Disclosure
Fair value of plan assets	13	17
Corporate bonds
Defined Benefit Plan Disclosure
Fair value of plan assets	60	66
Common/collective trusts
Defined Benefit Plan Disclosure
Fair value of plan assets		9
Bond funds
Defined Benefit Plan Disclosure
Fair value of plan assets	46	31
Blend funds
Defined Benefit Plan Disclosure
Fair value of plan assets		48
International funds
Defined Benefit Plan Disclosure
Fair value of plan assets	68
Common and preferred stocks
Defined Benefit Plan Disclosure
Fair value of plan assets	173	141
Other
Defined Benefit Plan Disclosure
Fair value of plan assets	29	31
Net Payables
Defined Benefit Plan Disclosure
Fair value of plan assets	3	5
Total pensions plan assets
Defined Benefit Plan Disclosure
Fair value of plan assets	1,642	343
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure
Fair value of plan assets	389
Level 1
Defined Benefit Plan Disclosure
Fair value of plan assets	300
Level 1 | U.S. government securities
Defined Benefit Plan Disclosure
Fair value of plan assets	13	17
Level 1 | Corporate bonds
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 1 | Common/collective trusts
Defined Benefit Plan Disclosure
Fair value of plan assets		0
Level 1 | Bond funds
Defined Benefit Plan Disclosure
Fair value of plan assets	46	31
Level 1 | Blend funds
Defined Benefit Plan Disclosure
Fair value of plan assets		48
Level 1 | International funds
Defined Benefit Plan Disclosure
Fair value of plan assets	68
Level 1 | Common and preferred stocks
Defined Benefit Plan Disclosure
Fair value of plan assets	173	141
Level 1 | Other
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 1 | Total pensions plan assets
Defined Benefit Plan Disclosure
Fair value of plan assets	300	237
Level 2
Defined Benefit Plan Disclosure
Fair value of plan assets	89
Level 2 | U.S. government securities
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 2 | Corporate bonds
Defined Benefit Plan Disclosure
Fair value of plan assets	60	66
Level 2 | Common/collective trusts
Defined Benefit Plan Disclosure
Fair value of plan assets		9
Level 2 | Bond funds
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 2 | Blend funds
Defined Benefit Plan Disclosure
Fair value of plan assets		0
Level 2 | International funds
Defined Benefit Plan Disclosure
Fair value of plan assets	0
Level 2 | Common and preferred stocks
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 2 | Other
Defined Benefit Plan Disclosure
Fair value of plan assets	29	31
Level 2 | Total pensions plan assets
Defined Benefit Plan Disclosure
Fair value of plan assets	89	106
Level 3
Defined Benefit Plan Disclosure
Fair value of plan assets	0
Level 3 | U.S. government securities
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 3 | Corporate bonds
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 3 | Common/collective trusts
Defined Benefit Plan Disclosure
Fair value of plan assets		0
Level 3 | Bond funds
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 3 | Blend funds
Defined Benefit Plan Disclosure
Fair value of plan assets		0
Level 3 | International funds
Defined Benefit Plan Disclosure
Fair value of plan assets	0
Level 3 | Common and preferred stocks
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 3 | Other
Defined Benefit Plan Disclosure
Fair value of plan assets	0	0
Level 3 | Total pensions plan assets
Defined Benefit Plan Disclosure
Fair value of plan assets	0	$ 0
Investments measured at net asset value
Defined Benefit Plan Disclosure
Fair value of plan assets	$ 1,253