Customer relationships expected benefit period.

No definition available.

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- Definition

Number of major customer.

+ References

No definition available.

+ Details

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- Definition

Organization consolidation and presentation of financial statements.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as operating activities. This may include cash restricted for regulatory purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
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-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586

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- Details

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- Details

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- Details

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- Details

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Description of Business and Basis of Presentation - Additional Information (Details) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Nov. 29, 2017 USD ($)	Oct. 31, 2017 USD ($) Customer	Oct. 31, 2016 Customer	Oct. 31, 2017 USD ($) Customer	Oct. 31, 2016 Customer	Jan. 31, 2017 USD ($) Customer
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Restricted cash		$ 26,543		$ 26,543		$ 26,781
Customer contracts, expected benefit period				5 years
Excess tax benefits from employee stock option exercises included in net operating loss and research and development tax credit forwards				$ 25,200
Subsequent Event
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Decrease in restricted cash	$ 26,000
Credit Concentration Risk \| Accounts Receivable
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of major customer \| Customer		1		1		2
Concentration risk percentage				10.00%		10.00%
Customer Concentration Risk \| Revenue
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of major customer \| Customer		0	0	0	0
Concentration risk percentage		10.00%	10.00%	10.00%	10.00%
Geographic Concentration Risk \| Revenue \| Non-U.S.
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Concentration risk percentage		79.00%	83.00%	21.00%	17.00%
Geographic Concentration Risk \| Revenue \| United States
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Concentration risk percentage		79.00%	83.00%	21.00%	17.00%
Geographic Concentration Risk \| Property and Equipment \| United States
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Concentration risk percentage				98.70%		99.70%