Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2013

Compensation and Retirement Disclosure [Abstract]

Components of net periodic cost (benefit)

Net Periodic Cost (Benefit)

Periods ended June 30	Three Months						Six Months
(In millions)	2013			2012			2013			2012
Pension cost (benefit)
Service cost	$	3		$	3		$	6		$	6
Interest cost on projected benefit obligation	30			33			60			67
Expected return on plan assets	(45		)	(42		)	(90		)	(85		)
Amortization of net actuarial (gain) loss	12			9			24			19
Net periodic pension cost (benefit)	$	—		$	3		$	—		$	7
Postretirement cost (benefit)
Interest cost on projected benefit obligation	$	1		$	1		$	1		$	1
Amortization of prior service credit	(5		)	(5		)	(9		)	(9		)
Net periodic postretirement cost (benefit)	$	(4	)	$	(4	)	$	(8	)	$	(8	)