Divestiture - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2019	Sep. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale	$ 0	$ 137
Advanced Bioprocessing
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business	$ 335
Disposal Group, Held-for-sale, Not Discontinued Operations | Advanced Bioprocessing
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale		$ 137