Lease Intangibles (Net Value of Other Intangible Assets and Amortization by Class) (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite Lived Intangible Assets [Line Items]
Lease intangibles	$ 13,383,080	$ 13,811,291	$ 13,845,100
Accumulated amortization	(8,501,656)	(7,944,757)	(5,829,342)
Lease intangibles, net	4,881,424	5,866,534	8,015,758
Leases, Acquired-in-Place [Member]
Finite Lived Intangible Assets [Line Items]
Lease intangibles	6,635,928	6,872,980	6,903,882
Accumulated amortization	(4,150,414)	(3,840,670)	(2,647,002)
Lease intangibles, net	2,485,514	3,032,310	4,256,880
Leasing Cost [Member]
Finite Lived Intangible Assets [Line Items]
Lease intangibles	4,622,792	4,813,951	4,816,858
Accumulated amortization	(2,709,250)	(2,517,759)	(1,766,578)
Lease intangibles, net	1,913,542	2,296,192	3,050,280
Above Market Leases [Member]
Finite Lived Intangible Assets [Line Items]
Lease intangibles	2,124,360	2,124,360	2,124,360
Accumulated amortization	(1,641,992)	(1,586,328)	(1,415,762)
Lease intangibles, net	$ 482,368	$ 538,032	$ 708,598

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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