MERGER AND SELF-MANAGEMENT TRANSACTION - Net Carrying Amount of Goodwill (FY) (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Combinations [Abstract]
Goodwill, net	$ 17,320,857	$ 17,320,857	$ 50,588,000

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Balance Type:	debit
Period Type:	instant