Mortgage Notes Payable - Summary (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019 USD ($) item	Dec. 31, 2018 USD ($) item loan
MORTGAGE NOTES PAYABLE
Long-term debt, gross	$ 392,009
Residential Property \| Mortgage Notes Payable
MORTGAGE NOTES PAYABLE
Number of mortgage loans out of compliance \| loan		9
Outstanding balance of loans out of compliance, in aggregate		$ 13,128
Fixed rate mortgage notes payable \| Mortgage Notes Payable
MORTGAGE NOTES PAYABLE
Long-term debt, gross	392,009	408,339
Less unamortized debt issuance costs	1,917	2,322
Long-term debt, net	390,092	406,017
Debt swapped from variable to fixed rate	$ 827	$ 865
Number of mortgage loans \| item	122	127
Fixed rate mortgage notes payable \| Mortgage Notes Payable \| Minimum
MORTGAGE NOTES PAYABLE
Effective interest rate (as a percent)	3.54%	3.44%
Fixed rate mortgage notes payable \| Mortgage Notes Payable \| Maximum
MORTGAGE NOTES PAYABLE
Effective interest rate (as a percent)	7.25%	7.25%
Fixed rate mortgage notes payable \| Mortgage Notes Payable \| Weighted Average
MORTGAGE NOTES PAYABLE
Effective interest rate (as a percent)	4.40%	4.42%

Represents the amount of mortgage debt swapped from variable rate to fixed rate.

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- Definition

Represents the number of mortgage notes payable out of compliance.

+ References

No definition available.

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- Definition

The principal amount outstanding, in aggregate, of the mortgage notes payable that are out of compliance as of the balance sheet date.

+ References

No definition available.

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- Definition

Represents the number of mortgage loans.

+ References

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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-Publisher FASB
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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