Divestitures and Other Transactions Divestitures and Other Transactions - Divested Ag Business Results of Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations after income taxes	$ 22	$ 526	$ (695)	$ 1,200
Specialty Products Disposal [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations before income taxes		519	(798)	1,521
Income (loss) from discontinued operations after income taxes	$ 22	$ 511	(880)	1,070
Divested Ag Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations before income taxes				(10)
Income (loss) from discontinued operations after income taxes			80	$ (5)
Other discontinued operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations after income taxes			$ 86