Borrowings (Pre-Swap Borrowing) (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 38,306		$ 39,737
Less: net unamortized discount	851		853
Add: fair value adjustment	911	[1]	792	[1]
Long-Term Debt, including current portion	38,367		39,675
Less: current maturities	4,072		4,601
Total long-term debt (excluding current portion)	34,295		35,073
U.S. dollar notes and debentures
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	30,884		31,404
1.20% Notes and Debentures, maturing in 2015-2016
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	6,859		9,254
Debt instrument, stated interest rate percentage (as a percent)	1.20%
Debt instrument, maturity year range, start	2015
Debt instrument, maturity year range, end	2016
3.90% Notes and Debentures, maturing in 2017-2018
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	8,709		6,835
Debt instrument, stated interest rate percentage (as a percent)	3.90%
Debt instrument, maturity year range, start	2017
Debt instrument, maturity year range, end	2018
2.20% Notes and Debentures, maturing in 2019-2021
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	6,555		6,555
Debt instrument, stated interest rate percentage (as a percent)	2.20%
Debt instrument, maturity year range, start	2019
Debt instrument, maturity year range, end	2021
1.88% Notes and Debentures, maturing in 2022
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	1,000		1,000
Debt instrument, stated interest rate percentage (as a percent)	1.88%
Debt instrument, maturity year	2022
3.38% Notes and Debentures, maturing in 2023
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	1,500		1,500
Debt instrument, stated interest rate percentage (as a percent)	3.38%
Debt instrument, maturity year	2023
3.63% Notes and Debentures, maturing in 2024
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	2,000		2,000
Debt instrument, stated interest rate percentage (as a percent)	3.63%
Debt instrument, maturity year	2024
7.00% Notes and Debentures, maturing in 2025
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	600		600
Debt instrument, stated interest rate percentage (as a percent)	7.00%
Debt instrument, maturity year	2025
6.22% Notes and Debentures, maturing in 2027
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	469		469
Debt instrument, stated interest rate percentage (as a percent)	6.22%
Debt instrument, maturity year	2027
6.50% Notes and Debentures, maturing in 2028
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	313		313
Debt instrument, stated interest rate percentage (as a percent)	6.50%
Debt instrument, maturity year	2028
5.88% Notes and Debentures, maturing in 2032
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	600		600
Debt instrument, stated interest rate percentage (as a percent)	5.88%
Debt instrument, maturity year	2032
8.00% Notes and Debentures, maturing in 2038
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	83		83
Debt instrument, stated interest rate percentage (as a percent)	8.00%
Debt instrument, maturity year	2038
5.60% Notes and Debentures, maturing in 2039
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	745		745
Debt instrument, stated interest rate percentage (as a percent)	5.60%
Debt instrument, maturity year	2039
4.00% Notes and Debentures, maturing in 2042
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	1,107		1,107
Debt instrument, stated interest rate percentage (as a percent)	4.00%
Debt instrument, maturity year	2042
7.00% Notes and Debentures, maturing in 2045
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	27		27
Debt instrument, stated interest rate percentage (as a percent)	7.00%
Debt instrument, maturity year	2045
7.13% Notes and Debentures, maturing in 2096
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	316		316
Debt instrument, stated interest rate percentage (as a percent)	7.13%
Debt instrument, maturity year	2096
1.9% Euros maturing in 2015 - 2025
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	4,843		5,463
Debt instrument, stated interest rate percentage (as a percent)	1.90%
Debt instrument, maturity year range, start	2015
Debt instrument, maturity year range, end	2025
2.8% Pound sterling maturing in 2017 - 2020
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	1,118		1,176
Debt instrument, stated interest rate percentage (as a percent)	2.80%
Debt instrument, maturity year range, start	2017
Debt instrument, maturity year range, end	2020
0.5% Japanese yen maturing in 2017-2019
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	732		733
Debt instrument, stated interest rate percentage (as a percent)	0.50%
Debt instrument, maturity year range, start	2017
Debt instrument, maturity year range, end	2019
3.8% Swiss francs maturing in 2015-2020
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	165		162
Debt instrument, stated interest rate percentage (as a percent)	3.80%
Debt instrument, maturity year range, start	2015
Debt instrument, maturity year range, end	2020
2.2% Canadian Maturing 2017
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	394		432
Debt instrument, stated interest rate percentage (as a percent)	2.20%
Debt instrument, maturity year	2017
9.8% Other maturing in 2015-2018
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 169		$ 367
Debt instrument, stated interest rate percentage (as a percent)	9.80%
Debt instrument, maturity year range, start	2015
Debt instrument, maturity year range, end	2018

[1] The portion of the company’s fixed-rate debt obligations that is hedged is reflected in the ConsolidatedStatement of Financial Position as an amount equal to the sum of the debt’s carrying value plus a fair value adjustment representing changes in the fair value of the hedged debt obligations attributable to movements in benchmark interest rates.