v3.21.1

Revenue and Contract Costs - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Jan. 31, 2021 | Jan. 31, 2020 | Jan. 31, 2019
Disaggregation of Revenue [Line Items] |  |  |
Subscription and related service revenues amortization period (in years) | 3 years |  |
Amortization expense | $ 2,025,000 | $ 1,977,000 | $ 1,640,000
Impairment loss | 0 | 0 | 0
Subscription and related services |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues recorded pursuant to ASC 842 | $ 6,312,000 | $ 5,985,000 | $ 4,749,000

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- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
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- Definition Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131251-203054 + Details
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- Definition Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
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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. + Details
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- Definition The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121549951&loc=d3e39896-112707 + Details
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- Details
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