Pension Plans and Other Post Employment Benefit Plans Basis of Fair Value Measurement (Details) - Pension Plan - USD ($) $ in Millions		Dec. 31, 2017	Aug. 31, 2017		Dec. 31, 2016	Dec. 31, 2015
Successor [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 20,284	$ 20,395	[1]
Fair Value of Plan Assets, Excluding Trust Receivables and payables and assets measured at NAV		17,765
Investments Measured at Net Asset Value		2,567
Pension Trust Receivables	[2]	127
Pension Trust Payables	[3]	(175)
Successor [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		10,961
Successor [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		6,643
Successor [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		161	181
Successor [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3,057
Successor [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3,057
Successor [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3,263
Successor [Member] | US Treasury and Government [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		497
Successor [Member] | US Treasury and Government [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,766
Successor [Member] | US Treasury and Government [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3,181
Successor [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		270
Successor [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,884
Successor [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		27	46
Successor [Member] | Asset-backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		706
Successor [Member] | Asset-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		17
Successor [Member] | Asset-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		687
Successor [Member] | Asset-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2	2
Successor [Member] | Hedge Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		85
Investments Measured at Net Asset Value		747
Successor [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		83
Successor [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2	0
Successor [Member] | Private Market Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		14
Investments Measured at Net Asset Value		1,383
Successor [Member] | Private Market Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Private Market Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Private Market Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		14	17
Successor [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		342
Investments Measured at Net Asset Value		437
Successor [Member] | Real Estate [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		239
Successor [Member] | Real Estate [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		7
Successor [Member] | Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		96	98
Successor [Member] | Derivative, Asset [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		24
Successor [Member] | Derivative, Asset [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3
Successor [Member] | Derivative, Asset [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		21
Successor [Member] | Derivative, Asset [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Derivative, Liability [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		(16)
Successor [Member] | Derivative, Liability [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Derivative, Liability [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		(16)
Successor [Member] | Derivative, Liability [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2
Successor [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2
Successor [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Successor [Member] | UNITED STATES | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[4]	4,043
Successor [Member] | UNITED STATES | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		4,012
Successor [Member] | UNITED STATES | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		14
Successor [Member] | UNITED STATES | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		17	16
Successor [Member] | Non-US [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3,064
Successor [Member] | Non-US [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,866
Successor [Member] | Non-US [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		195
Successor [Member] | Non-US [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3	2
Predecessor [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			19,685		$ 16,656	$ 17,497
Fair Value of Plan Assets, Excluding Trust Receivables and payables and assets measured at NAV					14,470
Investments Measured at Net Asset Value					2,294
Pension Trust Receivables	[5]				264
Pension Trust Payables	[6]				(372)
Predecessor [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					9,997
Predecessor [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					4,275
Predecessor [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			181		198	238
Predecessor [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					1,505
Predecessor [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					1,480
Predecessor [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					25
Predecessor [Member] | Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					2,067
Predecessor [Member] | US Treasury and Government [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					864
Predecessor [Member] | US Treasury and Government [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					1,203
Predecessor [Member] | US Treasury and Government [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					2,475
Predecessor [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					273
Predecessor [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					2,163
Predecessor [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			46		39	34
Predecessor [Member] | Asset-backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					721
Predecessor [Member] | Asset-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					39
Predecessor [Member] | Asset-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					682
Predecessor [Member] | Asset-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			2		0	1
Predecessor [Member] | Hedge Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					1
Investments Measured at Net Asset Value					434
Predecessor [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					1
Predecessor [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			0		0	0
Predecessor [Member] | Private Market Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					67
Investments Measured at Net Asset Value					1,416
Predecessor [Member] | Private Market Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | Private Market Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					25
Predecessor [Member] | Private Market Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			17		42	37
Predecessor [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					275
Investments Measured at Net Asset Value					444
Predecessor [Member] | Real Estate [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					175
Predecessor [Member] | Real Estate [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					2
Predecessor [Member] | Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			98		98	144
Predecessor [Member] | Derivative, Asset [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					53
Predecessor [Member] | Derivative, Asset [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					7
Predecessor [Member] | Derivative, Asset [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					46
Predecessor [Member] | Derivative, Asset [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | Derivative, Liability [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					(47)
Predecessor [Member] | Derivative, Liability [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | Derivative, Liability [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					(47)
Predecessor [Member] | Derivative, Liability [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					4
Predecessor [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					4
Predecessor [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					0
Predecessor [Member] | UNITED STATES | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[7]				4,071
Predecessor [Member] | UNITED STATES | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					4,033
Predecessor [Member] | UNITED STATES | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					20
Predecessor [Member] | UNITED STATES | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			16		18	20
Predecessor [Member] | Non-US [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					3,278
Predecessor [Member] | Non-US [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					3,126
Predecessor [Member] | Non-US [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets					151
Predecessor [Member] | Non-US [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			$ 2		1	$ 2
DowDuPont [Member] | Common Stock [Member] | Successor [Member] | UNITED STATES | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount of Employer and Related Party Securities Included in Plan Assets		$ 910
Amount of Employer and Related Party Securities Included in Plan Assets, Percent		4.00%
DuPont [Member] | Common Stock [Member] | Predecessor [Member] | UNITED STATES | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount of Employer and Related Party Securities Included in Plan Assets					$ 732
Amount of Employer and Related Party Securities Included in Plan Assets, Percent		4.00%

[1] The benefit obligation and the fair value of plan assets at the beginning of the period September 1 through December 31, 2017, reflects the remeasurement of the plans at the Merger Effectiveness Time.

[2] Primarily receivables for investments securities sold.

[3] Primarily payables for investment securities purchased

[4] The DuPont pension plans directly held $910 million (4 percent of total plan assets) of DowDuPont common stock at December 31, 2017.

[5] Primarily receivables for investments securities sold.

[6] Primarily payables for investment securities purchased.

[7] The DuPont pension plans directly held $732 million (4 percent of total plan assets) of DuPont common stock at December 31, 2016.