SHORT-TERM AND LONG-TERM DEBT (Details 2) $ in Thousands	Apr. 30, 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	199,400
Liability component, Unamortized discount	12,446
Liability component, Net carrying amount	186,954
Equity component, Net carrying amount	$ 43,131

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

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-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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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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Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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