Represents the number of debt instruments at the end of the period.

No definition available.

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- Definition

Represents the number of debt instruments repaid during the period.

+ References

No definition available.

+ Details

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- Definition

Represents the number of assumed loans refinanced.

+ References

No definition available.

+ Details

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- Definition

Represents the number of real estate properties on which the mortgage is created.

+ References

No definition available.

+ Details

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- Definition

Number of properties occupied by the applicable tenant associated with mortgages.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- 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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of long-term notes payable classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
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Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow from the repayments of a long-term debt originally issued by another party but is assumed by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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Mortgages Payable (Details) $ in Thousands	6 Months Ended		12 Months Ended
Mortgages Payable (Details) $ in Thousands	Jun. 30, 2018 USD ($) loan property	Jun. 30, 2017 USD ($) loan	Dec. 31, 2017 USD ($) loan property	Mar. 31, 2018 USD ($)
Debt
Weighted Average Stated Interest Rate	2.90%		4.50%
Mortgage Payable Balance	$ 311,708		$ 325,941
Mortgages Payable
Debt
Amount repaid	$ 13,400	$ 86,500
Number of assumed mortgages refinanced \| loan	0	0
Remaining balance of deferred financing costs at period end	$ 209		$ 236	$ 209
Number of Properties \| property	61		62
Weighted Average Stated Interest Rate	5.10%		5.00%
Weighted Average Effective Interest Rate (as a percent)	4.50%		4.40%
Weighted Average Remaining Years Until Maturity	3 years 7 months 6 days		4 years
Remaining Principal Balance	$ 306,836		$ 320,283
Unamortized Premium and Deferred Finance Costs Balance, net	4,872		5,658
Mortgage Payable Balance	$ 311,708		$ 325,941
Number of mortgages \| loan	27		28
Number of properties with mortgages \| property	61		62
Mortgages Payable \| Minimum
Debt
Weighted Average Effective Interest Rate (as a percent)	2.00%		2.60%
Stated interest rate (as a percent)	3.80%		3.40%
Mortgages Payable \| Maximum
Debt
Weighted Average Effective Interest Rate (as a percent)	6.00%		5.50%
Stated interest rate (as a percent)	6.90%		6.90%
Mortgages Payable \| Mortgages repaid in full
Debt
Amount repaid	$ 11,000	$ 82,900
Number of mortgages repaid \| loan	1	5
Mortgages Payable \| Variable rate mortgages
Debt
Remaining Principal Balance	$ 29,600		$ 29,900
Number of mortgages \| loan	3		3
Number of properties with mortgages \| property	3		3
Mortgages Payable \| Variable rate mortgages after interest rate arrangements
Debt
Remaining Principal Balance	$ 22,200		$ 22,400