DEBT - Mortgage Loan Payable (Q2) (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Face Value	$ 117,132,085	$ 134,022,937
Carrying Value	115,032,981	122,709,308
Fair Value	123,128,492	123,821,490
Mortgages
Debt Instrument [Line Items]
Face Value	$ 117,132,085	125,022,937	$ 62,228,409
Fair Value		$ 123,821,490	$ 62,363,284

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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