Merger-related Divestitures, Discontinued Operations and Net Assets Held for Sale - Schedule of Income from Discontinued Operations, Net of Tax (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations, net of tax	$ 89	$ 0
Noncontrolling interests	(7)	0
Income from discontinued operations, net of tax and noncontrolling interests	82	$ 0
Discontinued Operations, Disposed of by Sale | Linde AG Merger-Related Divestitures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	424
Cost of sales	247
Other operating costs	43
Operating profit	134
Income from equity investments	2
Income taxes	47
Income from discontinued operations, net of tax	89
Noncontrolling interests	(7)
Income from discontinued operations, net of tax and noncontrolling interests	$ 82