LONG-TERM DEBT (Long-term Debt) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Long-term debt, less current portion	$ 95,155	$ 723,888
Total debt	800,121
Less: current portion	655,874
5.00% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt	38,000
8.00% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt	55,000
5.75% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt	71,800	71,800
Carrying Value [Member]
Debt Instrument [Line Items]
Long-term debt, less current portion	95,155	723,888
Total debt	751,029	723,888
Less: current portion	655,874
Carrying Value [Member] \| Facility Agreement [Member]
Debt Instrument [Line Items]
Total debt	585,670	578,295
Carrying Value [Member] \| Subordinated Loan [Member]
Debt Instrument [Line Items]
Total debt	49,822	43,255
Carrying Value [Member] \| 5.00% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Total debt	16,701	13,077
Carrying Value [Member] \| 8.00% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Total debt	28,632	25,203
Carrying Value [Member] \| 5.75% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Total debt	70,204	64,058
Principal Amount [Member]
Debt Instrument [Line Items]
Debt	800,121	783,948
Less: current portion	657,474
Long term debt	142,647	783,948
Principal Amount [Member] \| Facility Agreement [Member]
Debt Instrument [Line Items]
Debt	585,670	578,295
Principal Amount [Member] \| Subordinated Loan [Member]
Debt Instrument [Line Items]
Debt	53,499	47,384
Principal Amount [Member] \| 5.00% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt	40,920	38,949
Principal Amount [Member] \| 8.00% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt	48,228	47,516
Principal Amount [Member] \| 5.75% Convertible Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt	$ 71,804	$ 71,804

Debt Instrument Face Amount Current

No definition available.

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- Definition

Debt Instruments Face Amount Noncurrent

+ References

No definition available.

+ Details

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

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-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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- Definition

Carrying amount of long-term debt, net of 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.

+ References

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 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Regulation S-X (SX)

-Number 210

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- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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