Stockholders' Equity Reclassifications out of AOCI (Details) - USD ($) $ in Millions		1 Months Ended		2 Months Ended	3 Months Ended													4 Months Ended	8 Months Ended	12 Months Ended
		Sep. 30, 2017		Aug. 31, 2017	Dec. 31, 2018		Sep. 30, 2018		Jun. 30, 2018		Mar. 31, 2018		Dec. 31, 2017		Jun. 30, 2017	Mar. 31, 2017		Dec. 31, 2017	Aug. 31, 2017	Dec. 31, 2018	Dec. 31, 2016
Successor [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of Goods Sold		$ 1,531	[1]		$ 3,980	[1]	$ 3,686	[1]	$ 5,669	[1]	$ 4,847	[1]	$ 4,709	[1]				$ 6,240		$ 18,182
Income Tax Expense (Benefit)																		(2,673)		220
(Loss) income from continuing operations after income taxes		$ (275)			$ (351)	[2],[3]	$ (4,960)	[3],[4]	$ 514	[3]	$ (216)	[3]	$ 1,362	[3]				1,087		(5,013)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																		0		0
Successor [Member] | Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of Goods Sold	[5]																	0		(6)
Income Tax Expense (Benefit)	[6]																	0		1
(Loss) income from continuing operations after income taxes																		0		(5)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																		0		(5)
Successor [Member] | Unrealized gain (loss) on investments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7]																	0		0
Reclassification from AOCI, Current Period, Tax	[6]																	0		0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																		0		0
Predecessor [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of Goods Sold				$ 1,937											$ 3,963	$ 4,152			$ 10,052		$ 13,937
Income Tax Expense (Benefit)																			149		641
(Loss) income from continuing operations after income taxes				$ (258)											$ 722	$ 1,178	[8],[9]		1,642		2,082
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																			321		335
Predecessor [Member] | Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of Goods Sold	[5]																		(21)		18
Income Tax Expense (Benefit)	[6]																		8		(7)
(Loss) income from continuing operations after income taxes																			(13)		11
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																			(13)		11
Predecessor [Member] | Unrealized gain (loss) on investments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7]																		(1)		28
Reclassification from AOCI, Current Period, Tax	[6]																		0		0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																			(1)		28
Pension Plan | Successor [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																		0		5
Pension Plan | Successor [Member] | Prior Service Benefit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																	0		0
Pension Plan | Successor [Member] | Actuarial Losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																	0		0
Pension Plan | Successor [Member] | Curtailment (loss) gain
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																	0		7
Pension Plan | Successor [Member] | Settlement loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																	0		(2)
Pension Plan | Successor [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax																		0		5
Reclassification from AOCI, Current Period, Tax	[6]																	0		0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																		0		5
Pension Plan | Predecessor [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																			325		594
Pension Plan | Predecessor [Member] | Prior Service Benefit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																		(3)		(6)
Pension Plan | Predecessor [Member] | Actuarial Losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																		506		822
Pension Plan | Predecessor [Member] | Curtailment (loss) gain
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																		0		40
Pension Plan | Predecessor [Member] | Settlement loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																		0		62
Pension Plan | Predecessor [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax																			503		918
Reclassification from AOCI, Current Period, Tax	[6]																		(178)		(324)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																			325		594
Other Benefit Plans | Successor [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																		0		0
Other Benefit Plans | Successor [Member] | Prior Service Benefit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																	0		0
Other Benefit Plans | Successor [Member] | Actuarial Losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																	0		0
Other Benefit Plans | Successor [Member] | Curtailment (loss) gain
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																	0		0
Other Benefit Plans | Successor [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax																		0		0
Reclassification from AOCI, Current Period, Tax	[6]																	0		0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																		$ 0		$ 0
Other Benefit Plans | Predecessor [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																			10		(298)
Other Benefit Plans | Predecessor [Member] | Prior Service Benefit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																		(46)		(134)
Other Benefit Plans | Predecessor [Member] | Actuarial Losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																		61		78
Other Benefit Plans | Predecessor [Member] | Curtailment (loss) gain
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[7],[10]																		0		(392)
Other Benefit Plans | Predecessor [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax																			15		(448)
Reclassification from AOCI, Current Period, Tax	[6]																		(5)		150
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax																			$ 10		$ (298)

[1] Includes charges of $(360) million and $(1,109) million, $(703) million, $(682) million, $(109) million, and $(134) million during the period September 1 - September 30, 2017, fourth quarter 2017, first quarter 2018, second quarter 2018, third quarter 2018, and fourth quarter 2018, respectively, related to the amortization of inventory step-up as a result of the Merger and the acquisition of the H&N Business. See Note 3 for additional information.

[2] Includes a loss on early extinguishment of debt of $(81) million in the fourth quarter 2018 related to the retirement of some of the company's notes payable. See Note 15 for additional information.

[3] Includes a tax benefit of $2,262 million in the fourth quarter 2017 related to The Act and a benefit related to an internal entity restructuring associated with the Intended Business Separations. Includes tax (charges) benefits of $(102) million, $(7) million, $46 million, and $(167) million in the first quarter 2018, second quarter 2018, third quarter 2018, and fourth quarter 2018, respectively, related to The Act. See Note 9 for additional information.

[4] Includes a tax charge of $(75) million in the third quarter 2018 related to the establishment of a full valuation allowance against the net deferred tax asset position of a legal entity in Brazil. See Note 9 for additional information.

[5] Cost of goods sold.

[6] Provision for (benefit from) income taxes from continuing operations.

[7] Sundry income (expense) - net.

[8] First quarter 2017 included a gain of $162 million recorded in sundry income - net associated with the sale of the company's global food safety diagnostic business. See Note 4 for additional information.

[9] First quarter 2017 included a tax benefit of $53 million, as well as a $47 million benefit on associated accrued interest reversals (recorded in sundry income (expense) - net), related to a reduction in the company’s unrecognized tax benefits due to the closure of various tax statutes of limitations.

[10] These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost of the company's pension and other benefit plans. See Note 18 for additional information.