PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Tables)

3 Months Ended

Mar. 31, 2021

Retirement Benefits [Abstract]

Net Periodic Benefit Cost for All Significant Plans

The following table provides the components of the Corporation's net periodic benefit cost (credit) for all significant plans:

Net Periodic Benefit Cost (Credit) for All Significant Plans	Three Months Ended
In millions	Mar 31, 2021		Mar 31, 2020
Defined Benefit Pension Plans
Service cost	$	8	$	9
Interest cost	19		28
Expected return on plan assets	(51)		(50)
Amortization of net loss	30		27
Curtailment gain	(7)		—
Net periodic benefit cost (credit)	$	(1)	$	14
Other Postretirement Benefit Plan
Interest cost	$	1	$	1
Amortization of net gain	(1)		(1)
Net periodic benefit cost	$	—	$	—