Postretirement Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2014

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

Effect on operations of the pension plans

Effect on Operations of Pension Plans
	Principal Pension Plans
	Three months ended March 31
(In millions)	2014		2013
Service cost for benefits earned	$	318	$	401
Prior service cost amortization		54		61
Expected return on plan assets		(801)		(875)
Interest cost on benefit obligation		686		614
Net actuarial loss amortization		641		912
Pension plans cost	$	898	$	1,113

	Other Pension Plans
	Three months ended March 31
(In millions)	2014		2013
Service cost for benefits earned	$	114	$	102
Prior service cost amortization		1		2
Expected return on plan assets		(197)		(165)
Interest cost on benefit obligation		146		130
Net actuarial loss amortization		49		86
Pension plans cost	$	113	$	155

Effect on operations of principal retiree health and life insurance plans

	Principal Retiree Health
	and Life Insurance Plans
	Three months ended March 31
(In millions)	2014		2013
Service cost for benefits earned	$	44	$	73
Prior service cost amortization		98		98
Expected return on plan assets		(12)		(15)
Interest cost on benefit obligation		110		107
Net actuarial loss (gain) amortization		(43)		4
Retiree benefit plans cost	$	197	$	267