Post-retirement and Similar Obligations (Tables)

3 Months Ended

Mar. 31, 2020

Retirement Benefits [Abstract]

Components of Net Periodic Pension and Postretirement Benefits

The components of net periodic benefit cost for pension benefits for the three months ended March 31, 2020 and 2019, respectively, consisted of:

	Three Months Ended March 31,
	2020			2019
(Millions)
Service cost	$	12		$	10
Interest cost	27			33
Expected return on plan assets	(50		)	(48		)
Amortization of:
Actuarial loss	31			30
Net Periodic Benefit Cost	$	20		$	25

The components of net periodic benefit cost for postretirement benefits for the three months ended March 31, 2020 and 2019, respectively, consisted of: 

	Three Months Ended March 31,
	2020			2019
(Millions)
Service cost	$	1		$	1
Interest cost	3			4
Expected return on plan assets	(2		)	(2		)
Amortization of:
Prior service costs	(2		)	(2		)
Net Periodic Benefit Cost	$	—		$	1