Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments And Contingencies Disclosure [Line Items]
Environmental liabilities		$ 3.9
Environmental remediation liabilities- discounted	$ 22.8	22.0
Accrual for environmental loss contingencies- weighted-average discount rate	3.50%
Environmental remediation liabilities- undiscounted	$ 61.1	59.5
Potential revision on future environmental remediation costs before tax	16.0
Rental expense	31.4	34.8	$ 31.9
Discontinued operations
Commitments And Contingencies Disclosure [Line Items]
Rental expense	$ 11.8	$ 10.2	$ 1.3