Mortgage Notes Payable, Revolving Credit Facility, and Term Loan Facility (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) property	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Encumbered properties \| property	94
Carrying Value	$ 509,395	$ 525,332
Deferred financing costs, net	$ (5,700)	0
Libor rate (as percent)	0.77%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Encumbered properties \| property	24
Carrying Value	$ 39,225	44,591
Fixed Rate Mortgage Loans [Member]
Debt Instrument [Line Items]
Encumbered properties \| property	52
Carrying Value	$ 378,477	427,334
Variable Rate Mortgage Loans [Member]
Debt Instrument [Line Items]
Encumbered properties \| property	18
Carrying Value	$ 71,707	33,044
Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Encumbered properties \| property	70
Carrying Value	$ 445,278	455,863
Premiums and discounts, net	217	392
Deferred financing costs, net	$ (5,123)	(4,907)
Variable rate Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Encumbered properties \| property	24
Carrying Value	$ 39,700	45,300
Deferred financing costs, net	$ (475)	(709)
Libor rate (as percent)	2.25%
Scheduled Maturity Dates	Aug. 07, 2018
Variable rate Term Loan Facility [Member]
Debt Instrument [Line Items]
Carrying Value	$ 25,000	25,000
Libor rate (as percent)	2.20%
Scheduled Maturity Dates	Oct. 05, 2020
Term Loan Facility [Member]
Debt Instrument [Line Items]
Carrying Value	$ 24,892	24,878
Deferred financing costs, net	$ (108)	$ (122)

Number of existing encumbered properties.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ 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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

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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.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28567-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 5: 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=6451184&loc=d3e28555-108399

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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

+ 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=6451184&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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