Commitments And Contingencies (Details) $ in Millions	9 Months Ended
Oct. 31, 2015 USD ($) landfill
Loss Contingencies [Line Items]
Loss Contingency, Range of Possible Loss, Maximum	$ 1.5
Loss Contingency, Estimate of Possible Loss	1.0
Loss Contingency Accrual	$ 1.0
Redfield Site [Member]
Loss Contingencies [Line Items]
Liability for on-site remediation, discounted rate	4.80%
On-site remediation liability, undiscounted basis	$ 15.4
Expected on-site remediation liability, year one	0.2
Expected on-site remediation liability, year two	0.2
Expected on-site remediation liability, year three	0.2
Expected on-site remediation liability, year four	0.2
Expected on-site remediation liability, year five	0.2
Expected on-site remediation liability, thereafter	14.4
Cumulative expenditures for both on-site and off-site remediation	27.6
Reserve for anticipated future remediation activities	9.8
Reserve for anticipated future remediation activities for on-site remediation	5.0
Reserve for anticipated future remediation activities for off-site remediation	4.8
Redfield Site Other Liabilities [Member]
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies in other liabilities	9.1
Redfield Site Other Accrued Expense [Member]
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies in other accrued expenses	$ 0.7
New York Tannery And Two Associated Landfills [Member]
Loss Contingencies [Line Items]
Liability for on-site remediation, discounted rate	6.40%
Expected on-site remediation liability, year one	$ 0.2
Expected on-site remediation liability, year two	0.2
Expected on-site remediation liability, year three	0.2
Expected on-site remediation liability, year four	0.2
Expected on-site remediation liability, year five	0.2
Expected on-site remediation liability, thereafter	0.8
Accrual for environmental loss contingencies in other liabilities	1.1
Accrual for environmental loss contingencies in other accrued expenses	$ 0.2
Number of associated landfills for which remediation efforts are completed \| landfill	2
Accrued liability to complete the cleanup, maintenance and monitoring at all sites	$ 1.3
Accrued liability on an undiscounted basis	$ 1.8

Accrual for environmental loss contingencies in other accrued expenses.

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Accrual for environmental loss contingencies in other liabilities.

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Cumulative environmental remediation expense.

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Remediation efforts completed for number of associated landfills.

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Reserve for anticipated future remediation activities.

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Reserve for anticipated future remediation activities for off site remediation.

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Reserve for anticipated future remediation activities for on site Remediation.

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Site contingency accrual on an undiscounted basis.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Undiscounted amount of the accrual for environmental loss contingencies.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of loss contingency liability.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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The estimated maximum amount of possible loss from the contingency.

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