Borrowings (Pre-Swap Borrowing) (Details 2) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 45,188	$ 38,820
Less: net unamortized discount	861	838
Less: unamortized debt issuance costs	95	74
Add: fair value adjustment	1,022	790
Long-Term Debt, including current portion	45,254	38,699
Less: current maturities	5,000	5,271
Total long-term debt (excluding current portion)	40,254	33,428
U.S. dollar notes and debentures
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	33,667	30,319
3.00% Notes and Debentures, maturing in 2016-2017
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 8,239	9,351
Debt instrument, stated interest rate percentage (as a percent)	3.00%
3.17% Notes and Debentures, maturing in 2018-2019
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 8,826	7,591
Debt instrument, stated interest rate percentage (as a percent)	3.17%
1.71% Notes and Debentures, maturing in 2020-2021
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 4,940	3,717
Debt instrument, stated interest rate percentage (as a percent)	1.71%
2.35% Notes and Debentures, maturing in 2022
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 1,901	1,900
Debt instrument, stated interest rate percentage (as a percent)	2.35%
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%
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%
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%
3.45% Notes and Debentures, maturing in 2026
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 1,350
Debt instrument, stated interest rate percentage (as a percent)	3.45%
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%
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%
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%
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%
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%
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%
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%
4.70% Notes and Debentures, maturing in 2046
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 650
Debt instrument, stated interest rate percentage (as a percent)	4.70%
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%
1.6% Euros maturing in 2016 - 2028
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 7,691	4,892
Debt instrument, stated interest rate percentage (as a percent)	1.60%
2.7% Pound sterling maturing in 2017 - 2022
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 1,514	1,555
Debt instrument, stated interest rate percentage (as a percent)	2.70%
0.4% Japanese yen maturing in 2017-2022
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 1,262	1,180
Debt instrument, stated interest rate percentage (as a percent)	0.40%
6.3% Swiss francs maturing in 2020
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 9	9
Debt instrument, stated interest rate percentage (as a percent)	6.30%
2.2% Canadian Maturing 2017
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 386	360
Debt instrument, stated interest rate percentage (as a percent)	2.20%
13.6% Other maturing in 2016-2020
Debt Disclosure
Aggregate carrying amount of long-term borrowings before adjusting for unamortized discount and fair value adjustment	$ 658	$ 506
Debt instrument, stated interest rate percentage (as a percent)	13.60%

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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-Publisher SEC
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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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