CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 30, 2015	Apr. 30, 2014
Cash flows from operating activities
Net income	$ 6,760us-gaap_ProfitLoss	$ 1,089us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	5,687us-gaap_DepreciationAndAmortization	4,227us-gaap_DepreciationAndAmortization
Equity based compensation	3,625us-gaap_ShareBasedCompensation	2,923us-gaap_ShareBasedCompensation
Tax benefit from exercise/vesting of equity awards	(317)	(4,290)
Deferred financing charges	182us-gaap_AmortizationOfFinancingCosts	180us-gaap_AmortizationOfFinancingCosts
Changes in operating assets and liabilities:
Accounts receivable, net	(10,883)	14,945
Inventories	54,099us-gaap_IncreaseDecreaseInInventories	37,010us-gaap_IncreaseDecreaseInInventories
Income taxes, net	(2,197)us-gaap_IncreaseDecreaseInIncomeTaxes	(9,722)us-gaap_IncreaseDecreaseInIncomeTaxes
Prepaid expenses and other current assets	692	(5,435)
Other assets, net	(1,216)	(2,036)
Accounts payable, accrued expenses and other liabilities	(92,505)	(42,214)
Net cash used in operating activities	(36,073)	(3,323)
Cash flows from investing activities
Capital expenditures	(7,690)	(10,125)
Net cash used in investing activities	(7,690)	(10,125)
Cash flows from financing activities
Proceeds from notes payable, net		14,107us-gaap_ProceedsFromNotesPayable
Proceeds from exercise of equity awards	303	558
Excess tax benefit from exercise/vesting of equity awards	317	4,290
Taxes paid for net share settlement		(4,316)
Noncontrolling interest investment		472
Net cash provided by financing activities	620	15,111
Foreign currency translation adjustments	497	(144)
Net increase (decrease) in cash and cash equivalents	(42,646)	1,519
Cash and cash equivalents at beginning of period	128,354	22,091
Cash and cash equivalents at end of period	85,708	23,610
Cash paid during the year for:
Interest	749us-gaap_InterestPaid	1,208us-gaap_InterestPaid
Income taxes	$ 5,804us-gaap_IncomeTaxesPaidNet	$ 6,055us-gaap_IncomeTaxesPaidNet

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