Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2013

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Summary of the components of net periodic benefit cost recognized for pension plans

		Qualified Plan				Nonqualified Plans
		Three Months Ended March 31,				Three Months Ended March 31,
		2013		2012		2013		2012
		(Dollars in millions)
Service cost		$	37	$	29	$	3	$	2
Interest cost			27		25		3		3
Estimated return on plan assets			(64)		(49)		―		―
Amortization and other			20		17		3		1
	Net periodic benefit cost	$	20	$	22	$	9	$	6