Significant Accounting Policies - Disaggregation of Revenue by Product Line (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2020	Feb. 01, 2019	Feb. 02, 2018
Disaggregation of Revenue [Line Items]
Net revenue	$ 552,765	$ 518,709	$ 467,930
Managed Security Solutions revenue
Disaggregation of Revenue [Line Items]
Net revenue	419,489	396,130	365,768
Security and Risk Consulting revenue
Disaggregation of Revenue [Line Items]
Net revenue	$ 133,276	$ 122,579	$ 102,162

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration