Consolidated Balance Sheets (FY) (Parenthetical) - $ / shares	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 11, 2017	Jul. 15, 2015
Preferred Stock (In USD Per Share)	$ 0.001	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized (In Shares)	50,000,000	50,000,000	50,000,000
Preferred Stock, Shares Issued (In Shares)	0	0	0
Preferred Stock, Shares Outstanding (In Shares)	0	0	0
Common Stock ( In USD Per Share)		$ 0.001
Common Class C
Common Stock ( In USD Per Share)	$ 0.001	$ 0.001	$ 0.001
Common Stock, Shares Authorized (In Shares)	300,000,000	300,000,000	200,000,000
Common Stock, Shares, Issued (In Shares)	15,313,171	12,943,294	8,838,002
Common Stock, Shares, Outstanding (In Shares)	15,313,171	12,943,294	8,838,002
Common Class S
Common Stock ( In USD Per Share)	$ 0.001	$ 0.001	$ 0.001
Common Stock, Shares Authorized (In Shares)	100,000,000	100,000,000	100,000,000	100,000,000	10,000,000
Common Stock, Shares, Issued (In Shares)	166,448	17,594	3,032
Common Stock, Shares, Outstanding (In Shares)	166,448	17,594	3,032

Face amount or stated value per share of common stock.

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