Discontinued Operations - Narrative (Details) - USD ($) shares in Millions		12 Months Ended
	Nov. 01, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 01, 2019	Aug. 01, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net pretax actuarial gain and prior service credit		$ 5,200,000	$ 5,400,000
After-tax actuarial gain and prior service credit		4,200,000	4,900,000
Estimated pre-tax actuarial gain to be recognized in the next fiscal year		1,000,000.0
Estimated prior service credit to be recognized in the next fiscal year		0
Payments of other discontinued reserves		24,400,000	27,800,000	$ 32,800,000
Workers’ compensation, product liability, and indemnification reserves
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payments of other discontinued reserves		3,800,000	5,400,000	2,400,000
Postretirement medical and life insurance benefits reserve, net
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payments of other discontinued reserves		400,000	1,100,000	1,000,000.0
Reserves for legal proceedings
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payments of other discontinued reserves		20,200,000	21,300,000	18,900,000
Discontinued Operations, Disposed of by Sale | Omega 3
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds on sale						$ 38,000,000
Discontinued Operations, Held-for-sale or Disposed of by Sale | FMC Health and Nutrition
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain from disposal, before tax	$ 918,000,000
Gain on sale of FMC Health and Nutrition, net of income taxes	$ 727,000,000	$ 0	$ 0	$ 727,100,000
Discontinued Operations, Held-for-sale | FMC Health and Nutrition
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Transitional services period	24 months
Transitional services period, optional extension	6 months
Livent
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Shares of common stock owned (in shares)					123