Note 12 - Debt (Details) - Long-term Debt - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Current portion of long-term debt and short-term borrowings
Current portion of long-term debt	$ 91	$ 36
Total current portion of long-term debt and short-term borrowings	572	36
Long-term debt
Long term debt	4,001	3,263
Long-term debt	3,910	3,227
Commercial Paper [Member]
Current portion of long-term debt and short-term borrowings
Commercial paper	481
Debentures, 8.875%, Due 2016 [Member]
Long-term debt
Debentures	64	66
Debentures, 1.45%, Due 2017 [Member]
Long-term debt
Debentures	250	250
Debentures 1.5%, Due 2018 [Member]
Long-term debt
Debentures	375
Debentures 6.625% Due 2019 [Member]
Long-term debt
Debentures	246	243
Debentures 4.25% Due 2020 [Member]
Long-term debt
Debentures	291	287
Debentures, 8.875%, Due 2021 [Member]
Long-term debt
Debentures	68	69
Debentures 2.9%, Due 2022 [Member]
Long-term debt
Debentures	374
Debentures, 3.70%, due 2023 [Member]
Long-term debt
Debentures	249	249
Medium Term Notes Average Rate 7.66% Due Through 2023 [Member]
Long-term debt
Debentures	45	45
Debentures 7.00% Due 2024 [Member]
Long-term debt
Debentures	99	99
Debentures 6.85% Due 2029 [Member]
Long-term debt
Debentures	169	170
Debentures Callable 7.25% Due 2036 [Member]
Long-term debt
Debentures	249	249
Debentures, 4.70%, Due 2037 [Member]
Long-term debt
Debentures	250	250
Debentures 5.75% Due 2040 [Member]
Long-term debt
Debentures	398	398
Debentures, 4.75%, Due 2042 [Member]
Long-term debt
Debentures	499	499
Other Average Rate 5.02%, Due Through 2042 [Member]
Long-term debt
Long term debt	$ 375	$ 389