Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2014

Compensation and Retirement Disclosure [Abstract]

Components of net periodic cost (benefit)

Net Periodic Cost (Benefit)

Three months ended March 31
(In millions)	2014			2013
Pension cost (benefit)
Service cost	$	3		$	3
Interest cost on projected benefit obligation	33			30
Expected return on plan assets	(48		)	(45		)
Amortization of net actuarial (gain) loss	6			12
Net periodic pension cost (benefit)	$	(6	)	$	—
Postretirement cost (benefit)
Amortization of prior service credit	$	(4	)	$	(4	)
Net periodic postretirement cost (benefit)	$	(4	)	$	(4	)