Consolidated Statement of Comprehensive Income - USD ($) $ in Millions		3 Months Ended			9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Consolidated Statement of Comprehensive Income [Abstract]
Net income (loss)		$ 1,873	$ 436		$ 4,427	$ (2,391)
Defined benefit plans
Reclassification adjustment for amortization of prior service cost (credit) included in net income		(10)	(9)		(30)	(28)
Net actuarial gain (loss) arising during the period		187	13		145	(26)
Reclassification adjustment for amortization of net actuarial losses included in net income		33	49		228	205
Other Comprehensive Income Loss NonSponsored Plan	[1]	0	0		(1)	0
Income taxes on defined benefit plans		(74)	(18)		(102)	(52)
Defined benefit plans, net of tax		136	35		240	99
Unrealized holding gain (loss) on securities		0	551		0	127
Income taxes on unrealized holding gain on securities		0	(45)		0	(45)
Unrealized holding loss on securities, net of tax		0	506	[2]	0	82	[2]
Foreign currency translation adjustments		59	509		(222)	720
Foreign currency translation adjustments, net of tax		59	509		(222)	720
Other Comprehensive Income (Loss), Net of Tax		195	1,050		18	901
Comprehensive Income (Loss)		2,068	1,486		4,445	(1,490)
Less: comprehensive income attributable to noncontrolling interests		(12)	(16)		(38)	(43)
Comprehensive Income (Loss) Attributable to ConocoPhillips		$ 2,056	$ 1,470		$ 4,407	$ (1,533)	[3]

[1] *Plans for which ConocoPhillips is not the primary obligor, primarily those administered by equity affiliates.

[2] **See Note 2—Changes in Accounting Principles and Note 16—Accumulated Other Comprehensive Loss for additional information relating to the adoption of ASU 2016-01.

[3] See Notes to Consolidated Financial Statements.