FAIR VALUE MEASUREMENTS (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Dec. 31, 2014
Minimum [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Foreign currency contracts duration	16 days
Maximum [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Foreign currency contracts duration	286 days
Designated as Hedging Instrument [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Contracts Revenue	3,940
Contracts Weighted Average Rate Price	1.23
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Before Tax	273
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	178
Gain (loss) recorded in Other Income for settled contracts	74
Canadian Dollar Forward Contracts [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Derivative asset, notional amount	3,181
Canadian Dollar Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Derivative, average forward exchange rate	1.17
Fair Value, Inputs, Level 2 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Insurance contracts fair value	3,392
Fair Value, Inputs, Level 2 [Member] \| Canadian Dollar Forward Contracts [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Gain (loss) on foreign currency derivative instruments not designated as hedging instruments	93
Convertible Notes 2017 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Debt instrument, interest rate, effective percentage	4.00%
Convertible Notes 2017 [Member] \| Fair Value, Inputs, Level 1 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Convertible debt, fair value disclosures	116,375
Senior Notes 2022 [Member] \| Fair Value, Inputs, Level 1 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Convertible debt, fair value disclosures	568,500
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Available-for-sale Securities	8,290
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Trading securities	1,320
Portion at Other than Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Available-for-sale Securities	8,400
Portion at Other than Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
FAIR VALUE MEASUREMENTS (Details) [Line Items]
Trading securities	1,000

Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Before Tax

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- Definition

Contracts weighted average rate price.

+ References

No definition available.

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- Definition

Time to expiration of outstanding foreign currency contracts.

+ References

No definition available.

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- Definition

Fair value of insurance contracts as of the reporting date.

+ References

No definition available.

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- Definition

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

Revenue earned during the period arising from products sold or services provided under the terms of a contract, not elsewhere specified in the taxonomy. May include government contracts, construction contracts, and any other contract related to a particular project or product.

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-Paragraph 2

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Convertible Security

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

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-Glossary Notional Amount

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- Definition

Average contractual rate at which a foreign currency can be purchased or sold.

+ References

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- Definition

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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- Definition

Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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- Definition

Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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