Legal Proceedings (Details)	1 Months Ended			3 Months Ended		9 Months Ended
	Feb. 28, 2017 USD ($)	Aug. 31, 2016 USD ($)	Jun. 30, 2016 USD ($)	Oct. 28, 2017 USD ($) Well	Oct. 29, 2016 USD ($)	Oct. 28, 2017 USD ($) Well	Oct. 29, 2016 USD ($)	May 19, 2017 employee	Jan. 28, 2017 USD ($)	Apr. 30, 2015 USD ($)
Loss Contingencies [Line Items]
Amount related to outstanding environmental contingencies				$ 2,900,000	$ 3,900,000	$ 2,900,000	$ 3,900,000		$ 4,400,000
Environmental contingency payment		$ 10,000,000
Pretax accrual charges (gains) for environmental contingencies included in provision for discontinued operations				$ 100,000	$ 100,000	$ 400,000	$ 200,000
Number of former employees seeking legal action | employee								2
Village of Garden City, New York
Loss Contingencies [Line Items]
Number of water supply wells | Well				2		2
Minimum historical cost associated with enhanced treatment required by the impact of groundwater plume						$ 1,800,000
Maximum historical cost associated with enhanced treatment required by the impact of groundwater plume						2,500,000
Future operation and maintenance costs						126,400
Amount awarded to other party			$ 10,000,000
Environmental Monitoring, Operation and Maintenance Activities | Village of Garden City, New York | Minimum
Loss Contingencies [Line Items]
Estimated possible loss				$ 1,700,000		1,700,000
Environmental Monitoring, Operation and Maintenance Activities | Village of Garden City, New York | Maximum
Loss Contingencies [Line Items]
Estimated possible loss				2,000,000		2,000,000
EPA Interim Oversight Costs | Village of Garden City, New York
Loss Contingencies [Line Items]
Estimated possible loss				$ 1,250,000		$ 1,250,000
Response Costs Claimed by the EPA
Loss Contingencies [Line Items]
Estimated possible loss										$ 2,200,000
Amount awarded to other party	$ 1,500,000
Estimated recovery percent from settlement	75.00%
Estimated recovery amount from a third party	$ 500,000