PENSION AND OTHER POST-EMPLOYMENT BENEFIT PLANS - Reconciliation of Pension Plan Assets Measured at Level 3 Fair Value (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)	$ 72	$ 99
Realized Gain (Loss)	0	3
Unrealized Gain (Loss)	11	(5)
Purchases, Sales, Settlements, Net	(5)	(18)
Transfers In (Out), Net	36	(7)
Fair value of plan assets at end of year (estimated)	114	72
Hedge funds and related investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)	4	13
Realized Gain (Loss)	0	3
Unrealized Gain (Loss)	0	(4)
Purchases, Sales, Settlements, Net	(1)	(9)
Transfers In (Out), Net	7	1
Fair value of plan assets at end of year (estimated)	10	4
Private equity and related investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year (estimated)	68	86
Realized Gain (Loss)	0	0
Unrealized Gain (Loss)	11	(1)
Purchases, Sales, Settlements, Net	(4)	(9)
Transfers In (Out), Net	29	(8)
Fair value of plan assets at end of year (estimated)	$ 104	$ 68