Commitments and Contingent Liabilities - Asbestos-Related Liabilities (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($) payment shares	Feb. 03, 2017 USD ($)	Dec. 31, 2016 USD ($)	Feb. 03, 2014 USD ($)
Other Commitments Chapter 11 [Abstract]
ZAI PD account funding				$ 34.4
ZAI P D Account, Payment on Third Anniversary of Effective Date of Joint Plan		$ 30.0
ZAI P D account, maximum number of contingent deferred payments | payment	10
ZAI P D account, deferred payments, each year for twenty years	$ 8.0
Period in which ZAI PD contingent deferred payments will be made	20 years
Minimum ZAI P D account assets for condition in relation to contingent obligation payments	$ 10.0
Frequency of PD trust payments	6 months
Number of shares issuable under warrant (in shares) | shares	77,372,257
Environmental remediation
Estimated liability for environmental investigative and remediation costs	$ 60.8		$ 66.3
Vermiculite Related Matters [Member]
Environmental remediation
Estimated liability for environmental investigative and remediation costs	26.6		31.2
Non-Vermiculite Related Matters [Member]
Environmental remediation
Estimated liability for environmental investigative and remediation costs	$ 34.2		$ 35.1