DERIVATIVES (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
DERIVATIVES
Notional amount of cash flow hedge swap agreements, low end of range	$ 8,462		$ 8,462
Notional amount of cash flow hedge swap agreements, high end of range	63,000		63,000
Strike rate cash flow hedge swap agreements, low end of range (as a percent)	4.24%		4.24%
Strike rate cash flow hedge swap agreements, high end of range (as a percent)	6.98%		6.98%
Cash flow hedge swap agreements increase (decrease) in interest expenses due to interest payments	(1,365)	(640)	(2,014)	(1,272)
Cash flow hedge swap agreements gain (loss) recognized in OCI			(674)
Cash flow hedge swap agreements gain (loss) reclassified from OCI			(2,014)
Fair value of cash flow hedge swap agreements	$ (6,748)		$ (6,748)		$ (6,074)

Represents the increase or decrease recognized in interest expenses due to interest payments under cash flow hedge swap agreements.

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- Definition

The high end of the range of the aggregate notional amount of all interest rate derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

+ Details

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- Definition

The low end of the range of the aggregate notional amount of all interest rate derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

+ Details

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- Definition

High end of the range of fixed interest rates when a range is presented for a group of interest rate derivatives.

+ Details

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- Details

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- Definition

Low end of the range of fixed interest rates when a range is presented for a group of interest rate derivatives.

+ Details

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- Definition

Fair value as of the balance sheet date of all interest rate derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 17
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

+ Details

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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(1)
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624171-113959

+ Details

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- Definition

Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 46
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624171-113959

+ Details

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