Employee Benefits (Tables)

6 Months Ended

Jun. 30, 2012

Employee Benefits [Abstract]

Components of net periodic benefit cost

	Three Months Ended June 30,												Six Months Ended June 30,
	Pension Plans						Postretirement Welfare Plan						Pension Plans						Postretirement Welfare Plan
(Dollars in Millions)	2012			2011			2012			2011			2012			2011			2012			2011
Service cost	$	32		$	29		$	1		$	1		$	64		$	59		$	2		$	2
Interest cost		42			42			2			2			84			84			4			4
Expected return on plan assets		(47	)		(51	)		(1	)		(1	)		(95	)		(103	)		(1	)		(2	)
Prior service cost (credit) and transition obligation (asset) amortization		(1	)		(3	)		—			—			(2	)		(5	)		—			—
Actuarial loss (gain) amortization		40			32			(2	)		(2	)		80			63			(4	)		(3	)
Net periodic benefit cost	$	66		$	49		$	—		$	—		$	131		$	98		$	1		$	1