Employee Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2018

Retirement Benefits [Abstract]

Net periodic benefit costs

The components of net periodic benefit costs, reported in other expenses, were as follows:

	Three Months Ended March 31,
	2018						2017
	Pension Benefits			Other Postretirement Benefits			Pension Benefits			Other Postretirement Benefits
	(In millions)
Service costs	$	60		$	1		$	61		$	1
Interest costs	96			11			106			19
Expected return on plan assets	(133		)	(18		)	(130		)	(18		)
Amortization of net actuarial (gains) losses	44			(8		)	49			—
Amortization of prior service costs (credit)	—			(5		)	—			(5		)
Net periodic benefit costs (credit)	$	67		$	(19	)	$	86		$	(3	)