Commitments and Contingencies - Summary of Accrual for Environmental Loss Contingencies (Details) $ in Thousands	6 Months Ended
Jul. 31, 2016 USD ($)
Site Contingency [Line Items]
Beginning balance	$ 5,330
Change in estimate	0
Utililzation	(113)
Ending balance	5,217
Accrued Liabilities [Member]
Site Contingency [Line Items]
Beginning balance	1,150
Change in estimate	(517)
Utililzation	(113)
Ending balance	520
Other Long-term Liabilities [Member]
Site Contingency [Line Items]
Beginning balance	4,180
Change in estimate	517
Utililzation	0
Ending balance	$ 4,697

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

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Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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Amount of cash outflow to settle environmental loss contingencies.

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