Business Combinations H&N Acquisition Narrative (Details) - USD ($) $ in Millions	1 Months Ended	2 Months Ended	3 Months Ended					4 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2018	Nov. 01, 2017	Aug. 31, 2017
Business Acquisition [Line Items]
Goodwill		$ 45,589	$ 40,686				$ 45,589	$ 45,589	$ 40,686
Successor [Member]
Business Acquisition [Line Items]
Net Sales	$ 1,735		5,741	$ 5,294	$ 8,545	$ 6,699	5,318	7,053	26,279
Loss from continuing operations before income taxes								(1,586)	(4,793)
Business Combination, Fair Value Step-Up Of Acquired Inventory, Amount recognized in Cost of Goods sold	$ 360		134	$ 109	$ 682	$ 703	1,109	1,469	1,628
Goodwill		45,589	$ 40,686				$ 45,589	$ 45,589	40,686		$ 45,105
H&N Business [Member] | Successor [Member]
Business Acquisition [Line Items]
Net Sales		102
Loss from continuing operations before income taxes		(12)
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Inventory, Finished Goods										$ 143
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Inventory, Semi-finished goods										85
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Raw Materials and stores and supplies										76
Business Combination, Fair Value Step Up Of Acquired Inventory										100
Business Combination, Fair Value Step-Up Of Acquired Inventory, Amount recognized in Cost of Goods sold		$ 35							$ 65
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment										489
Goodwill										732
Business Acquisition, Goodwill, Expected Tax Deductible Amount										208
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill										435
H&N Business [Member] | Machinery and Equipment [Member] | Successor [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment										356
H&N Business [Member] | Building [Member] | Successor [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment										63
H&N Business [Member] | Land and Land Improvements [Member] | Successor [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment										39
H&N Business [Member] | Construction in Progress [Member] | Successor [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment										31
H&N Business [Member] | Customer-Related Intangible Assets [Member] | Successor [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill										268
H&N Business [Member] | Developed Technology Rights [Member] | Successor [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill										130
H&N Business [Member] | Trademarks and Trade Names [Member] | Successor [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill										$ 37