DEBT (Details)	3 Months Ended	9 Months Ended
	Mar. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)
Secured and Unsecured Debt [Line Items]
Unsecured bank credit facilities, change during period		$ 43,745,000
Secured and unsecured debt [Member]
Payments of principal over future years [Abstract]
Remainder of 2015		29,313,000
2016		92,807,000
2017		58,239,000
2018		141,316,000
2019		130,569,000
2020 and beyond		383,471,000
Secured Debt [Member]
Secured and Unsecured Debt [Line Items]
Secured debt, change during period		(73,061,000)
Secured debt, amount repaid during period		57,450,000
Secured debt, principal payments during period		15,581,000
Amortization of Debt Discount (Premium)		30,000
Unsecured Debt [Member]
Secured and Unsecured Debt [Line Items]
Unsecured debt, change during period		$ 75,000,000
$75 million interest rate swap executed in 2015 [Member]
Secured and Unsecured Debt [Line Items]
Derivative, Notional Amount	$ 75,000,000
$75 million interest rate swap executed in 2015 [Member] | Unsecured Debt [Member]
Secured and Unsecured Debt [Line Items]
Long-term Debt, Maturities, Repayment Terms (in years)	7
Long-term debt, margin over LIBOR rate	1.40%
Effective Interest Rate	3.031%
Former credit facilities [Member]
Secured and Unsecured Debt [Line Items]
Margin over LIBOR rate (%)		1.175
Facility fee (%)		0.225
Loans Payable, Noncurrent [Abstract]
Debt Instrument, Maturity Date		Jan. 05, 2017
Current bank credit facilities [Member]
Secured and Unsecured Debt [Line Items]
Margin over LIBOR rate (%)		1.00
Facility fee (%)		0.20
Loans Payable, Noncurrent [Abstract]
Debt Instrument, Maturity Date		Jul. 30, 2019
Former Pnc na revolving credit facility [Member]
Secured and Unsecured Debt [Line Items]
Line of Credit Facility, Current Borrowing Capacity		$ 25,000,000
Former nine bank group unsecured revolving credit facility [Member]
Secured and Unsecured Debt [Line Items]
Line of Credit Facility, Current Borrowing Capacity		225,000,000
Nine bank group unsecured revolving credit facility [Member]
Secured and Unsecured Debt [Line Items]
Line of Credit Facility, Current Borrowing Capacity		300,000,000
Expansion option on credit facility		$ 150,000,000
Payments of principal over future years [Abstract]
Extension option on credit facility		1 year
Pnc Na Unsecured revolving credit facility [Member]
Secured and Unsecured Debt [Line Items]
Line of Credit Facility, Current Borrowing Capacity		$ 35,000,000
Payments of principal over future years [Abstract]
Extension option on credit facility		1 year