Employee Pension and Other Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2015

Compensation and Retirement Disclosure [Abstract]

Components of Net Periodic Benefit Cost

The following tables summarize the components of net periodic benefit cost for the three and nine months ended September 30, 2015 and 2014.

	Pension Benefits						Other Postretirement Benefits						Superannuation, SERP and ESBP
	For the Three Months Ended   September 30,						For the Three Months Ended   September 30,						For the Three Months Ended   September 30,
(Dollars in millions)	2015			2014			2015			2014			2015		2014
Components of net periodic benefit cost:
Service cost	$	24		$	21		$	4		$	2		$	—	$	—
Interest cost	27			25			4			3			—		1
Expected return on plan assets	(54		)	(49		)	(6		)	(5		)	—		—
Amortization of prior service cost	(4		)	(4		)	(2		)	(2		)	—		—
Recognized net actuarial loss	27			16			7			—			1		—
Total net periodic benefit cost	$	20		$	9		$	7		$	(2	)	$	1	$	1

	Pension Benefits						Other Postretirement Benefits						Superannuation, SERP and ESBP
	For the Nine Months Ended September 30,						For the Nine Months Ended September 30,						For the Nine Months Ended September 30,
(Dollars in millions)	2015			2014			2015			2014			2015		2014
Components of net periodic benefit cost:
Service cost	$	72		$	60		$	8		$	8		$	1	$	1
Interest cost	82			79			9			9			1		3
Expected return on plan assets	(162		)	(144		)	(15		)	(14		)	—		—
Amortization of prior service cost	(13		)	(7		)	(6		)	(3		)	—		—
Recognized net actuarial loss	80			43			9			1			2		1
Total net periodic benefit cost	$	59		$	31		$	5		$	1		$	4	$	5