RETIREMENT AND OTHER BENEFIT PROGRAMS - Amounts Expected to be Amortized from AOCI to Net Periodic Benefit Cost in 2019 (Details) $ in Millions	Dec. 31, 2019 USD ($)
Pension benefits
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss/(gain)	$ 78
Prior service credit and transition obligation	(1)
Total pre-tax amount expected to be amortized from AOCI to net pension and OPEB cost in 2019	77
OPEB
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss/(gain)	(4)
Prior service credit and transition obligation	(14)
Total pre-tax amount expected to be amortized from AOCI to net pension and OPEB cost in 2019	$ (18)