This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

INVESTMENTS IN UNCONSOLIDATED ENTITIES - Investments (Q2) (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Equity Method Investments	$ 13,987,073	$ 14,275,815	$ 14,524,022
RuMartin Street Santa Clara
Investment [Line Items]
Equity Method Investments	10,627,777	10,749,332
Rich Uncles Real Estate Investment Trust 1
Investment [Line Items]
Equity Method Investments	$ 3,359,296	$ 3,526,483