Real Estate Owned, Net - Component of lease expense (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Real Estate
Operating lease cost	$ 1,367,189	$ 1,115,204
Ground Lease
Real Estate
Operating lease cost	$ 316,125

Amount of operating lease expense. Excludes sublease income.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918638-209977

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration