POSTRETIREMENT BENEFIT PLANS (Tables)

3 Months Ended

Mar. 31, 2020

Retirement Benefits [Abstract]

Schedule of Effect on Operations of Pension Plans

	Principal pension plans							Other pension plans
	Three months ended March 31							Three months ended March 31
(In millions)	2020			2019				2020			2019
Service cost for benefits earned	$	153		$	158			$	65		$	63
Prior service cost amortization	37			33				—			—
Expected return on plan assets	(748		)	(863		)		(274		)	(284		)
Interest cost on benefit obligations	587			726				108			139
Net actuarial loss amortization	848			763				112			80
Curtailment/settlement loss (gain)	—			51			(a)	(1		)	9
Benefit plans cost	$	877		$	868			$	10		$	7

(a) Curtailment loss in the three months ended March 31, 2019, resulted from the spin-off and subsequent merger of our Transportation segment with Wabtec, which is included in Earnings (loss) from discontinued operations in our consolidated Statement of Earnings (Loss).