Related Party Transactions - Property Management and Board of Trustee Fees (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Related Party Transactions
Trustee fees	$ 51	$ 56
Unpaid board of trustee fees	$ 27	$ 32
GOLDMARK Property Management
Related Party Transactions
Property management fee, percent fee	5.00%	5.00%
Management fee, amount paid	$ 9,304	$ 6,439
Board Chairman - Board Meeting
Related Party Transactions
Shares received by board members per meeting	105
Trustee - Board Meeting
Related Party Transactions
Shares received by board members per meeting	75
Committee Chair - Committee Meeting
Related Party Transactions
Shares received by board members per meeting	30
Trustee - Committee Meeting
Related Party Transactions
Shares received by board members per meeting	30

Shares Paid To Board Members Per Meeting.

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- Definition

Amounts owed for trustee fees to the board of trustees.

+ References

No definition available.

+ Details

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- Definition

Amount of expenses related to the managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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- Definition

The percentage charged for managing real estate properties.

+ References

No definition available.

+ Details

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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

Fees charged annually for the professional services of a trustee, usually quoted as a percentage of the funds being managed. The fee for appointing an offshore Trustee is included in the trust price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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