Line items represent reporting 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.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

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INVESTMENTS IN UNCONSOLIDATED ENTITIES - Narrative (Q2) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Sep. 28, 2017
Investment [Line Items]
Distributions	$ 75,746	$ 68,316	$ 145,112	$ 136,632
Rich Uncles Real Estate Investment Trust 1
Investment [Line Items]
Ownership percentage ( as a percent )	4.80%		4.80%		4.80%	72.70%
Ownership Percentage by Noncontrolling Owners						27.30%
Dividends	$ 109,720	$ 136,849	$ 273,618	$ 316,535
Hagg Lane II, LLC \| Rich Uncles Real Estate Investment Trust 1
Investment [Line Items]
Ownership Percentage by Noncontrolling Owners						23.40%
Hagg Lane III, LLC \| Rich Uncles Real Estate Investment Trust 1
Investment [Line Items]
Ownership Percentage by Noncontrolling Owners						3.90%