Long-term Debt - Summary of Long-term Debt (Detail) - USD ($) $ in Millions		Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term debt, carrying amount		$ 17,538	$ 14,442
Commercial paper borrowings
Debt Instrument [Line Items]
Long-term debt, carrying amount		2,849	1,000
4.00% Senior Notes due 2025
Debt Instrument [Line Items]
Long-term debt, carrying amount		1,740	1,741
3.30% Senior Notes due 2021
Debt Instrument [Line Items]
Long-term debt, carrying amount		1,593	1,597
3.00% Senior Notes due 2020
Debt Instrument [Line Items]
Long-term debt, carrying amount		1,591	1,591
3.65% Senior Notes due 2023
Debt Instrument [Line Items]
Long-term debt, carrying amount		1,490	1,496
2.35% Senior Notes due 2018
Debt Instrument [Line Items]
Long-term debt, carrying amount		1,296	1,297
4.20% Senior Notes due 2021
Debt Instrument [Line Items]
Long-term debt, carrying amount		1,100	1,100
2.40% Senior Notes due 2022
Debt Instrument [Line Items]
Long-term debt, carrying amount		996	999
3.63% Senior Notes due 2022
Debt Instrument [Line Items]
Long-term debt, carrying amount		845	845
1.25% Senior Notes due 2017
Debt Instrument [Line Items]
Long-term debt, carrying amount			1,000
0.63% Guaranteed Notes due 2019
Debt Instrument [Line Items]
Long-term debt, carrying amount		668
1.50% Guaranteed Notes due 2019
Debt Instrument [Line Items]
Long-term debt, carrying amount		579	566
1.90% Senior Notes due 2017
Debt Instrument [Line Items]
Long-term debt, carrying amount		499	499
6.38% Notes due 2018
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	301
7.00% Notes due 2038
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	215
Other
Debt Instrument [Line Items]
Long-term debt, carrying amount		1,174	$ 711
4.50% Notes due 2021
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	138
5.95% Notes due 2041
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	116
3.60% Notes due 2022
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	110
5.13% Notes due 2043
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	99
4.00% Notes due 2023
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	83
3.70% Notes due 2024
Debt Instrument [Line Items]
Long-term debt, carrying amount	[1]	$ 56

[1] (1) Represents long-term fixed rate debt obligations assumed in connection with the acquisition of Cameron, net of amounts repurchased subsequent to the closing of the transaction.