Employee Benefits (Tables)

3 Months Ended

Mar. 31, 2017

Compensation and Retirement Disclosure [Abstract]

Schedule of components of net periodic pension benefit (income) expense and post-retirement benefit expense

Net periodic benefit expense (income) for our qualified and non-qualified pension plans included the following components:

	Pension Plans
	Three Months Ended March 31,
	2017			2016
	(Dollars in millions)
Service cost	$	17		17
Interest cost	101			107
Expected return on plan assets	(166		)	(184	)
Recognition of prior service credit	(2		)	(2	)
Recognition of actuarial loss	51			42
Net periodic pension benefit expense (income)	$	1		(20	)

Net periodic benefit expense for our post-retirement benefit plans included the following components:

	Post-Retirement Benefit Plans
	Three Months Ended March 31,
	2017		2016
	(Dollars in millions)
Service cost	$	4	5
Interest cost	25		28
Expected return on plan assets	—		(2	)
Recognition of prior service cost	5		5
Net periodic post-retirement benefit expense	$	34	36