Impairment and Restructuring Costs - (Details) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($) Employee	Dec. 31, 2015 USD ($) Employee	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Restructuring Cost and Reserve [Line Items]
Impairment charges	$ 1,160	$ 1,436	$ 0	$ 0
Weighted average cost of capital (percent)	9.80%
Impaired machinery and equipment	$ 1,320
Restructuring Costs		830
Inventory Write-down		194
Inventory Write Down-Cost of Sales		37
Inventory Write Down-Cost of Services		157
Workforce reductions [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs		436
Benefit plan curtailment gains		$ 10
Restructuring and Related Cost, Number of Positions Eliminated | Employee		18,000
Restructuring and Related Cost, Number of Positions Eliminated, Inception to Date | Employee	17,000	17,000
Payments for Restructuring		$ 365
Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Other Restructuring Costs		121
Payments for Restructuring		81
Prepayments Write-Off		14
Impairment of buildings and improvements
Restructuring Cost and Reserve [Line Items]
Impaired machinery and equipment		82
Impairment of machinery and equipment
Restructuring Cost and Reserve [Line Items]
Impaired machinery and equipment		191
Machinery and Equipment
Restructuring Cost and Reserve [Line Items]
Carrying Amount of Impaired Long-Lived Assets, Held-for-use	$ 1,640	1,640
Impaired machinery and equipment	1,050
Customer Relationships and Trade Names [Member]
Restructuring Cost and Reserve [Line Items]
Carrying Amount of Intangible Assets, Finite-Lived	178	$ 178
Impaired intangible assets	$ 116