XML 94 R71.htm IDEA: XBRL DOCUMENT
v3.20.1

Note 13 - Leases (Details Textual) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Jan. 31, 2020 | Jan. 31, 2019 | Jan. 31, 2018
Operating Lease, Expense |  | $ 5.2 | $ 5.1
Minimum [Member] |  |  |
Lessee, Operating Lease, Remaining Lease Term | 1 year |  |
Maximum [Member] |  |  |
Lessee, Operating Lease, Remaining Lease Term | 9 years |  |
Lessee, Operating Lease, Renewal Term | 3 years |  |

X
- Definition The remaining lease term for operating lease of lessee. + References No definition available. + Details
Name: | dsgx_LesseeOperatingLeaseRemainingLeaseTerm
Namespace Prefix: | dsgx_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of lessee's operating lease renewal, 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 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of operating lease expense. Excludes sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977 + Details
Name: | us-gaap_OperatingLeaseExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |