Contingencies - Asbestos - Rollforward of number of plaintiffs - (Details) - lawsuit	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Approximate number of plaintiffs and claimants asbestos claims pending against the entity
Pending at beginning of year (in number of litigants)	1,070	1,330	1,400
Disposed (in number of litigants)	1,170	1,220	1,320
Filed (in number of litigants)	950	960	1,250
Pending at end of year (in number of litigants)	850	1,070	1,330