Commitments and Contingent Liabilities - Summary of Asbestos Claims Activity (Details) - Asbestos Related Product Liability $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($) claim	Dec. 31, 2018 USD ($) claim
Number of claims filed
Pending claims, beginning of period	43,100	54,300
New claims filed	400	1,300
Claims settled/dismissed	(300)	(12,500)
Pending claims, end of period	43,200	43,100
Payments | $	$ 2	$ 13