PENSIONS AND OTHER POSTRETIREMENT BENEFITS (Tables)

3 Months Ended

Mar. 31, 2021

Postemployment Benefits [Abstract]

Schedule of Net Benefit Costs

The following are the components of defined benefit pension and OPEB costs (credits):

Defined Benefit Pension Costs (Credits)

	(In Millions)
	Three Months Ended March 31,
	2021		2020
Service cost	$	14	$	5
Interest cost	26		8
Expected return on plan assets	(90)		(18)
Amortization:
Net actuarial loss	8		7
Net periodic benefit cost (credit)	$	(42)	$	2

OPEB Costs (Credits)

	(In Millions)
	Three Months Ended March 31,
	2021		2020
Service cost	$	13	$	1
Interest cost	18		2
Expected return on plan assets	(10)		(5)
Amortization:
Prior service credits	—		(1)
Net actuarial loss	1		1
Net periodic benefit cost (credit)	$	22	$	(2)