Financial Risk Management Activities - Corporate Financial Risk Management Activities - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($) MMBbls	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) MMBbls	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Derivative Instruments Gain Loss [Line Items]
After-tax deferred gains in Accumulated other comprehensive income (loss)	$ (1,518,000,000)		$ (1,518,000,000)		$ (1,704,000,000)
Change in fair value of interest rate swaps - increase/(decrease)	54,000,000	$ 0	56,000,000	$ 0
Designated as Cash Flow Hedges | Maximum
Derivative Instruments Gain Loss [Line Items]
Interest rate swaps reclassified into earnings during next 12 months	1,000,000		1,000,000
Interest Rate Swaps
Derivative Instruments Gain Loss [Line Items]
Outstanding gross notional amount	995,000,000		995,000,000		350,000,000
Interest Rate Swaps | Designated as Fair Value Hedges
Derivative Instruments Gain Loss [Line Items]
Outstanding gross notional amount	450,000,000		450,000,000		350,000,000
Unrealized change in fair value of interest rate swaps - increase/(decrease)	2,000,000	4,000,000	3,000,000	18,000,000
Interest Rate Swaps | Designated as Cash Flow Hedges
Derivative Instruments Gain Loss [Line Items]
Outstanding gross notional amount	545,000,000		545,000,000
Change in fair value of interest rate swaps - increase/(decrease)	1,000,000		1,000,000
Accumulated other comprehensive income (loss) reclassified into earnings before noncontrolling interests	1,000,000		1,000,000
Foreign Exchange
Derivative Instruments Gain Loss [Line Items]
Outstanding gross notional amount	54,000,000		54,000,000		785,000,000
Total foreign exchange gains and (losses) reported in Other, net in Revenues and Non-Operating Income in the Statement of Consolidated Income	10,000,000	15,000,000	9,000,000	21,000,000
Gain (Loss) on foreign exchange contracts not designated as hedging instruments	2,000,000	33,000,000	2,000,000	13,000,000
After tax foreign currency translation adjustments included in Accumulated other comprehensive income (loss)	73,000,000	$ (27,000,000)	87,000,000	$ 142,000,000
Accumulated cumulative currency translation adjustment	(958,000,000)		(958,000,000)		$ (1,045,000,000)
Crude Oil Collars
Derivative Instruments Gain Loss [Line Items]
Increased (decreased) sales and other operating revenue	(12,000,000)		(11,000,000)
Gain (loss) E&P sales reclassified from other comprehensive income			20,000,000
After-tax deferred gains in Accumulated other comprehensive income (loss)	$ 56,000,000		$ 56,000,000
Outstanding gross notional amount, in millions of barrels | MMBbls	0		0