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Borrowings and Lines of Credit (Long-term Debt Obligations) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Nov. 30, 2014
Debt Instrument [Line Items]
Long-term debt	$ 4,265	$ 3,877
Commercial paper	459	935
Capital lease obligations	30	33
Long-term debt and capital lease obligations	4,296	3,899
Less payments due within one year	254	366
Long-term debt	$ 4,042	$ 3,533
Effective interest rates	3.10%	3.90%
Notes 3.875 Percent Due 2015
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 363
Debt instrument, interest rate, stated percentage	3.875%
Notes 1.9 Percent Due 2016
Debt Instrument [Line Items]
Long-term debt	$ 250	249
Debt instrument, interest rate, stated percentage	1.90%
3-year Variable Rate Euro Bank Loan Due 2017
Debt Instrument [Line Items]
Long-term debt	$ 544	605
Notes 6.65 Percent Due 2018
Debt Instrument [Line Items]
Long-term debt	$ 125	125
Debt instrument, interest rate, stated percentage	6.65%
Notes 2.3 Percent Due 2019
Debt Instrument [Line Items]
Long-term debt	$ 297	297
Debt instrument, interest rate, stated percentage			2.30%
Notes 3.6 Percent Due 2020
Debt Instrument [Line Items]
Long-term debt	$ 496	494
Debt instrument, interest rate, stated percentage	3.60%
Non-callable Debentures 9 Percent Due 2021
Debt Instrument [Line Items]
Long-term debt	$ 133	133
Debt instrument, interest rate, stated percentage	9.00%
Notes 0.875 Percent Due 2022
Debt Instrument [Line Items]
Long-term debt	$ 647	0
Debt instrument, interest rate, stated percentage	0.0875%
Notes 1.4 Percent Due 2027
Debt Instrument [Line Items]
Long-term debt	$ 641	0
Debt instrument, interest rate, stated percentage	1.40%
Notes 2.5 Percent Due 2029
Debt Instrument [Line Items]
Long-term debt	$ 86	95
Debt instrument, interest rate, stated percentage			2.50%
Notes 7.70 Percent Due 2038
Debt Instrument [Line Items]
Long-term debt	$ 174	174
Debt instrument, interest rate, stated percentage	7.70%
Notes 5.5 Percent Due 2040
Debt Instrument [Line Items]
Long-term debt	$ 246	246
Debt instrument, interest rate, stated percentage	5.50%
Notes 3.0 Percent Due 2044
Debt Instrument [Line Items]
Long-term debt	$ 122	136
Debt instrument, interest rate, stated percentage			3.00%
Impact Of Derivatives On Debt
Debt Instrument [Line Items]
Long-term debt	4	9
Other Non US Debt, Weighted Average
Debt Instrument [Line Items]
Long-term debt	$ 42	$ 5
Debt instrument, interest rate, stated percentage	6.10%	2.30%