SHORT-TERM AND LONG-TERM DEBT (Details 2) $ in Thousands	Jan. 31, 2016 USD ($)
0.875% Convertible Senior Notes due June 15, 2017
Debt Instrument [Line Items]
Repurchased face amount	$ 14,100
Convertible Notes Payable \| 4.0% Convertible Senior Notes due December 15, 2020
Debt Instrument [Line Items]
Liability component, Principal balance	198,489
Liability component, Unamortized discount	12,906
Liability component, Net carrying amount	185,583
Equity component, Net carrying amount	$ 43,131

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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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.

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Face (par) amount of the original debt instrument that was repurchased.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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