Benefit Plans (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Benefit Plans
Maximum annual medical cost inflation after retirement for Company's share of retiree medical benefits cost for non Medicare-eligible retirees (as a percent)	5.00%
Items not yet recognized as a component of net periodic cost
Deferred income taxes	$ (635,000,000)	$ (597,000,000)
Unrecognized pension and other postretirement benefit cost	638,000,000	1,729,000,000
Pension benefits
Components of net periodic cost
Fair value of plan assets	5,602,000,000	5,398,000,000	4,675,000,000
Less: Benefit obligation	5,297,000,000	6,727,000,000	5,831,000,000
Funded status	305,000,000	(1,329,000,000)
Items not yet recognized as a component of net periodic cost
Net actuarial loss (gain)	1,794,000,000	2,892,000,000
Prior service credit	(480,000,000)	(1,000,000)
Unrecognized pension and other postretirement benefit cost, pre-tax	1,314,000,000	2,891,000,000
Deferred income taxes	(460,000,000)	(1,012,000,000)
Unrecognized pension and other postretirement benefit cost	854,000,000	1,879,000,000
Increase (decrease) in defined benefit net actuarial loss arising during the period	1,100,000,000
Increase (decrease) in defined benefit plan	479,000,000
Change in items not yet recognized as a component of defined benefit plans, net periodic cost
Items not yet recognized as a component of net periodic cost, at the beginning of the period	2,891,000,000
Net actuarial gain arising during the period	(579,000,000)
Net actuarial (loss) gain amortized to net periodic benefit cost	(512,000,000)
Prior service credit arising during the period	(506,000,000)
Prior service credit amortized to net periodic benefit cost	28,000,000
Translation adjustment and other	(8,000,000)
Items not yet recognized as a component of net periodic cost, at the end of the period	1,314,000,000	2,891,000,000
Estimates of the net actuarial loss (gain) and prior service credit expected to be recognized as a component of net periodic benefit cost during 2012
Net actuarial loss (gain)	115,000,000
Prior service credit	(58,000,000)
Accumulated benefit obligation (ABO)	5,230,000,000	6,090,000,000
Company's Pension Plans with an ABO in excess of plan assets
Company's pension plans with ABO in excess of plan assets, aggregate projected benefit obligation	146,000,000	6,350,000,000
Company's pension plans with ABO in excess of plan assets, aggregate accumulated benefit obligation	145,000,000	5,750,000,000
Company's pension plans with ABO in excess of plan assets, aggregate fair value of plan assets	0	5,020,000,000
Defined benefit plans' accrued benefit costs related to certain unfunded and non-qualified plans	146,000,000	146,000,000
Change in benefit obligation
Benefit obligation, beginning of year	6,727,000,000	5,831,000,000
Service cost	140,000,000	152,000,000	151,000,000
Interest cost	265,000,000	298,000,000	322,000,000
Participant contributions	1,000,000	1,000,000
Actuarial (gain) loss	(406,000,000)	756,000,000
Benefits paid	(892,000,000)	(312,000,000)
Plan amendments	(506,000,000)
Translation adjustment and other	(31,000,000)	1,000,000
Curtailment gain	(1,000,000)
Benefit obligation, end of year	5,297,000,000	6,727,000,000	5,831,000,000
Components of net periodic cost
Service cost	140,000,000	152,000,000	151,000,000
Interest cost	265,000,000	298,000,000	322,000,000
Expected return on plan assets	(394,000,000)	(393,000,000)	(367,000,000)
Amortization of prior service credit	(28,000,000)	(2,000,000)	(2,000,000)
Amortization of net actuarial loss (gain)	235,000,000	178,000,000	154,000,000
Settlement loss	277,000,000	33,000,000	46,000,000
Net periodic cost (credit)	495,000,000	266,000,000	304,000,000
Weighted average assumptions used to determine net pension cost and net postretirement benefit cost
Discount rate (as a percent)	4.60%	5.25%	6.00%
Rate of increase in compensation levels, low end of the range (as a percent)			4.00%
Rate of increase in compensation levels, high end of the range (as a percent)			4.50%
Rate of increase in compensation levels	3.50%	4.50%
Expected weighted average long-term rate of return on plan assets (as a percent)	7.75%	8.50%	8.50%
Weighted average assumptions used to determine benefit obligations
Discount rate (as a percent)	5.00%	4.00%
Rate of increase in compensation levels	3.50%	3.50%
Pension plan assets
Fair value of plan assets, beginning of year	5,398,000,000	4,675,000,000
Actual return on plan assets	566,000,000	594,000,000
Employer contribution	561,000,000	439,000,000
Benefits paid	(892,000,000)	(312,000,000)
Translation adjustment and other	(31,000,000)	2,000,000
Fair value of plan assets, end of year	5,602,000,000	5,398,000,000	4,675,000,000
Postretirement benefits
Components of net periodic cost
Less: Benefit obligation	482,000,000	803,000,000	716,000,000
Funded status	(482,000,000)	(803,000,000)
Items not yet recognized as a component of net periodic cost
Net actuarial loss (gain)	(236,000,000)	(115,000,000)
Prior service credit	(106,000,000)	(129,000,000)
Unrecognized pension and other postretirement benefit cost, pre-tax	(342,000,000)	(244,000,000)
Deferred income taxes	126,000,000	94,000,000
Unrecognized pension and other postretirement benefit cost	(216,000,000)	(150,000,000)
Increase (decrease) in defined benefit net actuarial loss arising during the period	121,000,000
Change in items not yet recognized as a component of defined benefit plans, net periodic cost
Items not yet recognized as a component of net periodic cost, at the beginning of the period	(244,000,000)
Net actuarial gain arising during the period	(32,000,000)
Net actuarial (loss) gain amortized to net periodic benefit cost	16,000,000
Prior service credit amortized to net periodic benefit cost	23,000,000
Plan curtailment	(104,000,000)
Translation adjustment and other	(1,000,000)
Items not yet recognized as a component of net periodic cost, at the end of the period	(342,000,000)	(244,000,000)
Estimates of the net actuarial loss (gain) and prior service credit expected to be recognized as a component of net periodic benefit cost during 2012
Net actuarial loss (gain)	(22,000,000)
Prior service credit	(23,000,000)
Change in benefit obligation
Benefit obligation, beginning of year	803,000,000	716,000,000
Service cost	12,000,000	13,000,000	11,000,000
Interest cost	28,000,000	36,000,000	37,000,000
Participant contributions	18,000,000	20,000,000
Actuarial (gain) loss	(32,000,000)	76,000,000
Benefits paid	(57,000,000)	(59,000,000)
Translation adjustment and other	(5,000,000)	1,000,000
Curtailment gain	(285,000,000)
Benefit obligation, end of year	482,000,000	803,000,000	716,000,000
Components of net periodic cost
Service cost	12,000,000	13,000,000	11,000,000
Interest cost	28,000,000	36,000,000	37,000,000
Amortization of prior service credit	(23,000,000)	(23,000,000)	(23,000,000)
Amortization of net actuarial loss (gain)	(16,000,000)	(20,000,000)	(30,000,000)
Settlement loss			1,000,000
Curtailment gain	(181,000,000)
Net periodic cost (credit)	(180,000,000)	6,000,000	(4,000,000)
Weighted average assumptions used to determine net pension cost and net postretirement benefit cost
Discount rate (as a percent)	3.75%	5.25%	6.00%
Weighted average assumptions used to determine benefit obligations
Discount rate (as a percent)	4.85%	4.25%
Defined benefit plan, assumed health care cost trend rates
Defined Benefit plan, Weighted average health care cost trend rate (as a percent)	7.00%
Defined Benefit plan, ultimate health care cost trend rate in 2024 and thereafter (as a percent)	4.50%
Increase in the total of service and interest cost components of net periodic benefit cost due to one percentage-point increase in assumed health care cost trend rates	2,000,000
Increase in APBO due to one percentage-point increase in assumed health care cost trend rates	21,000,000
Decrease in APBO due to one percentage-point decrease in assumed health care cost trend rates	2,000,000
Decrease in the total of service and interest cost components of net periodic benefit cost due to one percentage-point decrease in assumed health care cost trend rates	19,000,000
Pension plan assets
Employer contribution	39,000,000	39,000,000
Benefits paid	$ (57,000,000)	$ (59,000,000)