Commitments and Contingencies (Narrative) (Details) - Redfield Site [Member] $ in Millions	9 Months Ended
Oct. 28, 2017 USD ($)
Loss Contingencies [Line Items]
Cumulative expenditures for both on-site and off-site remediation	$ 29.7
Environmental Exit Costs, Assets Previously Disposed, Liability for Remediation	9.6
Reserve for anticipated future remediation activities for on-site remediation	4.6
Reserve for anticipated future remediation activities for off-site remediation	$ 5.0
Liability for on-site remediation, discounted rate	4.80%
On-site remediation liability, undiscounted basis	$ 14.1
Expected on-site remediation liability, year one	0.1
Expected on-site remediation liability, year two	0.1
Expected on-site remediation liability, year three	0.1
Expected on-site remediation liability, year four	0.1
Expected on-site remediation liability, year five	0.2
Expected on-site remediation liability, thereafter	13.5
Other Noncurrent Liabilities [Member]
Loss Contingencies [Line Items]
Environmental Exit Costs, Assets Previously Disposed, Liability for Remediation	8.7
Other Current Liabilities [Member]
Loss Contingencies [Line Items]
Environmental Exit Costs, Assets Previously Disposed, Liability for Remediation	$ 0.9

Cumulative environmental remediation expense.

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Reserve for anticipated future remediation activities for off site remediation.

+ References

No definition available.

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Reserve for anticipated future remediation activities for on site Remediation.

+ References

No definition available.

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- Definition

Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 450
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-Section S99
-Paragraph 1
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Undiscounted amount of the accrual for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q1)
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-Paragraph 7
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- Definition

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.

+ References

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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.

+ References

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- Definition

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.

+ References

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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.

+ References

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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.

+ References

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- Definition

Carrying amount of the liability for remediation of environmental damage pertaining to assets or businesses previously disposed.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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