XML 78 R63.htm IDEA: XBRL DOCUMENT
v3.8.0.1

CONCENTRATION (Detail Textuals) | 12 Months Ended
--- | ---
Jan. 31, 2018 | Jan. 31, 2017 | Jan. 31, 2016
Customer |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of concentration risk | 22.20% | 21.80% | 20.80%
Supplier |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of concentration risk | 65.10% | 72.00% | 77.70%
Vendors |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of concentration risk |  | 23.90% | 25.20%
Vendors | One Vendor |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of concentration risk | 14.70% | 13.60% | 13.00%
Vendors | Two Vendor |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of concentration risk |  | 10.30% | 12.20%

X
- 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 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611 + Details
Name: | us-gaap_ConcentrationRiskPercentage1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_EntityWideRevenueMajorCustomerLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_SupplierConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=giii_VendorConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | giii_MajorVendorAxis=giii_OneVendorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | giii_MajorVendorAxis=giii_TwoVendorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |