Employee Benefit Plans (Tables)

6 Months Ended

Jun. 30, 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 June 30,
	2018						2017
	Pension Benefits			Other Postretirement Benefits			Pension Benefits			Other Postretirement Benefits
	(In millions)
Service costs	$	58		$	2		$	61		$	2
Interest costs	96			15			106			19
Expected return on plan assets	(134		)	(18		)	(128		)	(18		)
Amortization of net actuarial (gains) losses	44			(9		)	48			—
Amortization of prior service costs (credit)	—			(4		)	(1		)	(6		)
Net periodic benefit costs (credit)	$	64		$	(14	)	$	86		$	(3	)

	Six Months Ended June 30,
	2018						2017
	Pension Benefits			Other Postretirement Benefits			Pension Benefits			Other Postretirement Benefits
	(In millions)
Service costs	$	118		$	3		$	122		$	3
Interest costs	192			26			212			38
Expected return on plan assets	(267		)	(36		)	(258		)	(36		)
Amortization of net actuarial (gains) losses	88			(17		)	97			—
Amortization of prior service costs (credit)	—			(9		)	(1		)	(11		)
Net periodic benefit costs (credit)	$	131		$	(33	)	$	172		$	(6	)