Defined Benefit Postretirement Plans (Tables)

3 Months Ended

Mar. 31, 2018

Defined Benefit Postretirement Plans Disclosure [Abstract]

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

The following summarizes the components of net periodic benefit cost:

	Three Months Ended March 31,
	Pension Benefits						Other Benefits
(In millions)	2018			2017			2018			2017
Service cost	$	4		$	6		$	1		$	1
Interest cost	7			8			2			2
Expected return on plan assets	(9		)	(12		)	—			—
Amortization:
– prior service cost (credit)	(2		)	(2		)	(2		)	(2		)
– actuarial loss	3			2			—			—
Net settlement loss (a)	4			14			—			—
Net periodic benefit cost	$	7		$	16		$	1		$	1

^(a)  Settlements are recognized as they occur, once it is probable that lump sum payments from a plan for a given year will exceed the plan’s total service and interest cost for that year.