Risk-free interest rate assumption used in valuing an instrument.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

The increase (decrease) during the period in the carrying value of derivative instruments reported as liabilities that are due to be disposed of within one year (or the normal operating cycle, if longer).

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 3: 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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Article 5

-Subsection 19, 20, 22

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FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Jan. 09, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unsecured notes payable	$ 350,000us-gaap_UnsecuredDebt	$ 250,000us-gaap_UnsecuredDebt
Fair value of interest rate swap	2,391	1,448
Interest Rate Swap
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Decrease in valuation of interest rate swaps	943
Interest Rate Swap \| Deferred Credits and Other Liabilities
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value of interest rate swap	2,391
Amended and Restated Credit Facility
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unsecured notes payable			100,000
Fair Value, Inputs, Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value of interest rate swap	$ 2,391	$ 1,448
Fair Value, Inputs, Level 2 \| Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value assumptions, interest rate	3.37%
Fair Value, Inputs, Level 2 \| Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value assumptions, interest rate	5.51%