Business Combinations Merger with Dow Narrative (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	2 Months Ended	3 Months Ended							4 Months Ended	8 Months Ended	12 Months Ended
		Aug. 31, 2017	Sep. 30, 2017	Aug. 31, 2017	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Aug. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Aug. 30, 2017
Merger with Dow [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 74,680
Equity Awards converted but not yet earned		144
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Inventory, Finished Goods		4,929		$ 4,929									$ 4,929
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Inventory, Semi-finished goods		3,055		3,055									3,055
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Raw Materials and stores and supplies		823		823									823
Property, plant and equipment		11,941		11,941									11,941
Goodwill	[1]	45,105		$ 45,105									$ 45,105
Deferred Taxes, Business Combination, Adjustment To Derecognize Valuation Allowance		172
Deferred Taxes, Business Combination, Adjustment For Reinvestment Strategy		$ 546
DuPont [Member]
Business Acquisition [Line Items]
Common Stock, Par or Stated Value Per Share																$ 0.30
DuPont [Member] | $4.50 Series Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred Stock, Par or Stated Value Per Share																4.50
DuPont [Member] | $3.50 Series Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred Stock, Par or Stated Value Per Share																$ 3.50
DowDuPont [Member]
Business Acquisition [Line Items]
Common Stock, Par or Stated Value Per Share		$ 0.01		$ 0.01									$ 0.01
Common Stock [Member] | Merger with Dow [Member]
Business Acquisition [Line Items]
Share exchange ratio, DuPont to DowDuPont		1.2820
Machinery and Equipment [Member] | Merger with Dow [Member]
Business Acquisition [Line Items]
Property, plant and equipment		$ 7,466		$ 7,466									$ 7,466
Building [Member] | Merger with Dow [Member]
Business Acquisition [Line Items]
Property, plant and equipment		2,583		2,583									2,583
Construction in Progress [Member] | Merger with Dow [Member]
Business Acquisition [Line Items]
Property, plant and equipment		980		980									980
Land and Land Improvements [Member] | Merger with Dow [Member]
Business Acquisition [Line Items]
Property, plant and equipment		912		912									912
Successor [Member]
Business Acquisition [Line Items]
Common Stock, Par or Stated Value Per Share					$ 0.30							$ 0.30
Business Combination, Fair Value Step-Up Of Acquired Inventory, Amount recognized in Cost of Goods sold			$ 360		$ 1,109							$ 1,469
Goodwill		45,105		45,105	45,589							45,589	45,105
Integration and Separation Costs			$ (71)		$ (243)							314
Successor [Member] | Merger with Dow [Member]
Business Acquisition [Line Items]
Business Combination, Fair Value Step-Up Of Acquired Inventory Recognized Including Discontinued Operations												1,538
Business Combination, Fair Value Step-Up Of Acquired Inventory, Amount recognized in Cost of Goods sold												1,434
Disposal Group, Including Discontinued Operations, Fair Value Step-Up Of Acquired Inventory Recognized												$ 104
Predecessor [Member]
Business Acquisition [Line Items]
Common Stock, Par or Stated Value Per Share								$ 0.30						$ 0.30
Goodwill		$ 4,543		4,543				$ 4,169					4,543	$ 4,169	$ 4,238
Integration and Separation Costs						$ (201)	$ (170)	$ (164)	$ (122)	$ (76)	$ (24)		$ 581	$ 386	$ 10
Predecessor [Member] | Merger with Dow [Member]
Business Acquisition [Line Items]
Integration and Separation Costs				$ (210)

[1] See Note 12 for additional information.