LONG-TERM DEBT LIABILITIES (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Senior unsecured notes	$ 220,000,000
Current amount of long-term debt	(10,724,000)	(3,000,000)
Total long-term debt	$ 481,973,000	$ 514,124,000
Stated interest rate percentage, senior unsecured debt	0.105%

Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher SEC

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-Number 210

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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