Mortgage Notes Payable - Summary (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) item	Dec. 31, 2019 USD ($) item Lender
MORTGAGE NOTES PAYABLE
Long-term debt, gross	$ 396,922
Residential Property \| Mortgage Notes Payable
MORTGAGE NOTES PAYABLE
Number of mortgage loans out of compliance \| item		10
Outstanding balance of loans out of compliance, in aggregate		$ 16,361
Outstanding balance of mortgage loans out of compliance in which annual waivers were received from the lenders		$ 10,435
Number of lenders in which annual waivers were not received for loans out of compliance \| Lender		1
Outstanding balance of mortgage loans out of compliance in which annual waivers were not received from the lender		$ 5,926
Fixed rate mortgage notes payable \| Mortgage Notes Payable
MORTGAGE NOTES PAYABLE
Long-term debt, gross	396,922	395,038
Less unamortized debt issuance costs	1,848	1,874
Long-term debt, net	395,074	393,164
Debt swapped from variable to fixed rate	$ 16,079	$ 12,960
Number of mortgage loans \| item	121	121
Fixed rate mortgage notes payable \| Mortgage Notes Payable \| Minimum
MORTGAGE NOTES PAYABLE
Effective interest rate (as a percent)	3.15%	3.15%
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)	4.30%	4.31%

The number of lenders in which annual waivers were not received for loans out of compliance.

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

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The outstanding balance of mortgage loans out of compliance in which annual waivers were not received from the lenders.

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The outstanding balance of mortgage loans out of compliance in which annual waivers were received from the lenders.

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Represents the number of mortgage notes payable out of compliance.

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

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Represents the number of mortgage loans.

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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

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

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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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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
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-Name Accounting Standards Codification
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