Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. 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
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- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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UNSECURED NOTES PAYABLE (Details) - USD ($)	9 Months Ended
UNSECURED NOTES PAYABLE (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Outstanding balance of debt	$ 887,956,000	$ 1,050,051,000
Revolving Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Amount repaid on subscription line	20,800,000
Debt instrument face amount	150,000,000.0
Long-term line of credit	0
Line of Credit \| Unsecured Debt
Debt Instrument [Line Items]
Amount repaid on subscription line	50,000,000
Line of Credit \| Unsecured Term Loan Maturing June 27, 2021 \| Unsecured Debt
Debt Instrument [Line Items]
Debt instrument face amount	150,000,000.0
Line of Credit \| Unsecured Term Loan Maturing January 4, 2021 \| Unsecured Debt
Debt Instrument [Line Items]
Debt instrument face amount	50,000,000.0
Fund II \| Line of Credit
Debt Instrument [Line Items]
Amount borrowed on unsecured credit facility	12,500,000
Long-term line of credit	25,000,000
Fund IV \| Line of Credit
Debt Instrument [Line Items]
Amount borrowed on unsecured credit facility	5,600,000
Long-term line of credit	40,100,000
Fund IV \| Line of Credit \| Subscription Line
Debt Instrument [Line Items]
Amount repaid on subscription line	47,800,000
Outstanding balance of debt	$ 44,100,000
LIBOR \| Revolving Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Basis spread on variable rate	1.40%
LIBOR \| Line of Credit \| Unsecured Term Loan Maturing June 27, 2021 \| Unsecured Debt
Debt Instrument [Line Items]
Basis spread on variable rate	1.30%
LIBOR \| Line of Credit \| Unsecured Term Loan Maturing January 4, 2021 \| Unsecured Debt
Debt Instrument [Line Items]
Basis spread on variable rate	1.30%