CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (LOSS) (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Apr. 30, 2015	Apr. 30, 2014
Income Statement [Abstract]
Net sales	$ 432,965us-gaap_SalesRevenueGoodsNet	$ 366,192us-gaap_SalesRevenueGoodsNet
Cost of goods sold	278,538us-gaap_CostOfGoodsSold	236,058us-gaap_CostOfGoodsSold
Gross profit	154,427us-gaap_GrossProfit	130,134us-gaap_GrossProfit
Selling, general and administrative expenses	137,034	122,441
Depreciation and amortization	5,687	4,227
Operating profit	11,706us-gaap_OperatingIncomeLoss	3,466us-gaap_OperatingIncomeLoss
Interest and financing charges, net	975us-gaap_FinancingInterestExpense	1,709us-gaap_FinancingInterestExpense
Income before income taxes	10,731	1,757
Income tax expense	3,971us-gaap_IncomeTaxExpenseBenefit	668us-gaap_IncomeTaxExpenseBenefit
Net income	6,760us-gaap_ProfitLoss	1,089us-gaap_ProfitLoss
Add: Loss attributable to noncontrolling interest		201
Income attributable to G-III	6,760us-gaap_NetIncomeLoss	1,290us-gaap_NetIncomeLoss
Basic:
Net income per common share (in dollars per share)	$ 0.15us-gaap_EarningsPerShareBasic	$ 0.03us-gaap_EarningsPerShareBasic
Weighted average number of shares outstanding (in shares)	44,965	40,976
Diluted:
Net income per common share (in dollars per share)	$ 0.15us-gaap_EarningsPerShareDiluted	$ 0.03us-gaap_EarningsPerShareDiluted
Weighted average number of shares outstanding (in shares)	46,210	42,044
Net income attributable to G-III	6,760us-gaap_NetIncomeLoss	1,290us-gaap_NetIncomeLoss
Other comprehensive loss:
Foreign currency translation adjustments	(11,124)	(36)
Other comprehensive loss	(11,124)	(36)
Comprehensive income (loss)	$ (4,364)	$ 1,254

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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