DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Summary of the Notional Amount and Fair Value of Derivatives) (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Aug. 01, 2019	Jun. 27, 2019	May 01, 2019	Dec. 31, 2018	Sep. 21, 2018
Fair value of derivative instruments
Total fair value derivative assets	$ 0	$ 0				$ 346,000
Total fair value derivative liabilities	(48,788,000)	(48,788,000)				(16,517,000)
Interest income	0	200,000
Construction Loans
Fair value of derivative instruments
Loan amount			$ 64,600,000
Construction Loans | 8770 New Trails
Fair value of derivative instruments
Loan amount				$ 35,500,000
Interest rate cap | Derivative instruments not designated as hedging instruments | Prepaid expenses and other assets, net | Fixed Interest Rate 2.50%, Maturing December 2019
Fair value of derivative instruments
Notional amount	$ 230,000,000	$ 230,000,000
Fixed interest rate	2.50%	2.50%
Total fair value derivative assets	$ 0	$ 0				333,000
Interest rate cap | Derivative instruments designated as hedging instruments
Fair value of derivative instruments
Notional amount	230,000,000.0	230,000,000.0
Interest rate cap | Derivative instruments designated as hedging instruments | Prepaid expenses and other assets, net | Fixed Interest Rate 5.0% Maturing August 2019
Fair value of derivative instruments
Notional amount	$ 75,000,000	$ 75,000,000
Fixed interest rate	5.00%	5.00%
Total fair value derivative assets	$ 0	$ 0				0
Interest rate collar | Derivative instruments designated as hedging instruments | Prepaid expenses and other assets, net | Fixed Interest Rate 1.50% To 2.50%, Maturing May 2019
Fair value of derivative instruments
Notional amount	51,592,000	51,592,000			$ 51,600,000
Total fair value derivative assets	0	0				13,000
Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.00% To 3.00%, Maturing May 2020
Fair value of derivative instruments
Notional amount, liability	193,967,000	193,967,000
Total fair value derivative liabilities	(254,000)	(254,000)				(37,000)
Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.25% To 3.25%, Maturing May 2021
Fair value of derivative instruments
Notional amount, liability	354,217,000	354,217,000
Total fair value derivative liabilities	(2,521,000)	(2,521,000)				(730,000)
Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.75% To 3.50%, Maturing April 2022
Fair value of derivative instruments
Notional amount, liability	381,404,000	381,404,000
Total fair value derivative liabilities	(5,367,000)	(5,367,000)				(1,969,000)
Interest rate swap contracts | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.96%, Maturing September 2023
Fair value of derivative instruments
Notional amount, liability	$ 615,000,000	$ 615,000,000
Fixed interest rate	2.96%	2.96%
Total fair value derivative liabilities	$ (37,378,000)	$ (37,378,000)				(13,781,000)
Interest rate swap contracts | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 4.89% Maturing January 2032
Fair value of derivative instruments
Notional amount, liability	$ 1,810,000	$ 1,810,000
Fixed interest rate	4.89%	4.89%
Total fair value derivative liabilities	$ (3,268,000)	$ (3,268,000)				$ 0
Minimum | Interest rate collar | Derivative instruments designated as hedging instruments | Prepaid expenses and other assets, net | Fixed Interest Rate 1.50% To 2.50%, Maturing May 2019
Fair value of derivative instruments
Fixed interest rate	1.50%	1.50%
Minimum | Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.00% To 3.00%, Maturing May 2020
Fair value of derivative instruments
Fixed interest rate	2.00%	2.00%
Minimum | Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.25% To 3.25%, Maturing May 2021
Fair value of derivative instruments
Fixed interest rate	2.25%	2.25%
Minimum | Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.75% To 3.50%, Maturing April 2022
Fair value of derivative instruments
Fixed interest rate	2.75%	2.75%
Maximum | Interest rate collar | Derivative instruments designated as hedging instruments | Prepaid expenses and other assets, net | Fixed Interest Rate 1.50% To 2.50%, Maturing May 2019
Fair value of derivative instruments
Fixed interest rate	2.50%	2.50%
Maximum | Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.00% To 3.00%, Maturing May 2020
Fair value of derivative instruments
Fixed interest rate	3.00%	3.00%
Maximum | Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.25% To 3.25%, Maturing May 2021
Fair value of derivative instruments
Fixed interest rate	3.25%	3.25%
Maximum | Interest rate collar | Derivative instruments designated as hedging instruments | Accounts payable and accrued expenses | Fixed Interest Rate 2.75% To 3.50%, Maturing April 2022
Fair value of derivative instruments
Fixed interest rate	3.50%	3.50%
$700 Million Loan Maturity September 2023 | Term Loan
Fair value of derivative instruments
Loan amount							$ 615,000,000.0