Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stock-based compensation awards
Vesting period of awards issued prior to 2015, after the date of grant (in years)	3 years
Required minimum age of a participant upon separation from service to meet the criteria for Long Service Separation (in years)	55 years
Minimum term of service to meet criteria for Long Service Separation (in years)	5 years
Requisite service period prior to 2015 grant (in months)	6 months
Term life of SARs and option awards (in years)	10 years
Term life of vested options/SARs from separation date (in years)	5 years
Stock-based compensation expense, before tax (in dollars)	$ 48	$ 70	$ 240	$ 207
Granted, Stock options (in shares)			7,939,497	4,448,218
Weighted-Average Fair Value Per Award, Stock options (in dollars per share)			$ 23.61	$ 29.52
Weighted-Average Grant Date Stock Price (in dollars per share)	$ 83.34	$ 96.31	$ 83.34	$ 96.31
Assumptions used in determining the fair value of the stock-based awards
Weighted-average dividend yield (as a percent)			2.27%	2.15%
Weighted-average volatility (as a percent)			28.40%	28.20%
Volatilities, low end of range (as a percent)			19.90%	18.40%
Volatilities, high end of range (as a percent)			35.90%	36.20%
Risk-free interest rates, low end of range (as a percent)			0.22%	0.12%
Risk-free interest rates, high end of range (as a percent)			2.08%	2.60%
Weighted-average expected lives (in years)			8 years	8 years
Unrecognized compensation cost related to nonvested stock-based compensation awards (in dollars)	$ 261		$ 261
Term of amortization of unrecognized compensation cost over weighted-average remaining requisite service periods (in years)			2 years
RSUs
Stock-based compensation awards
Granted (in shares)			1,822,729	1,429,512
Weighted-Average Fair Value Per Award, RSUs (in dollars per share)			$ 77.54	$ 89.18
Weighted-Average Grant Date Stock Price (in dollars per share)	$ 83.01	$ 96.31	$ 83.01	$ 96.31
2015 Grant
Stock-based compensation awards
Graded vesting period of awards granted (in years)	3 years
2015 Grant | Percentage of award vested on first anniversary of grant date
Stock-based compensation awards
Portion of the award vested on each anniversary of the grant date	33.33%
2015 Grant | Percentage of award vested on second anniversary of grant date
Stock-based compensation awards
Portion of the award vested on each anniversary of the grant date	33.33%
2015 Grant | Percentage of award vested on third anniversary of grant date
Stock-based compensation awards
Portion of the award vested on each anniversary of the grant date	33.33%