Loans - Secured Loans by Property Type (Details)		3 Months Ended	12 Months Ended
		Mar. 31, 2018 USD ($) MortgageLoan	Dec. 31, 2017 USD ($) MortgageLoan
Loans (Details) - Secured Loans by Property Type [Line Items]
Loans | MortgageLoan		93	93
Loans - principal (in Dollars) | $		$ 57,865,391	$ 54,768,689
Loans - percent		100.00%	100.00%
Single Family [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Loans | MortgageLoan	[1]	65	67
Loans - principal (in Dollars) | $	[1]	$ 37,929,509	$ 37,615,216
Loans - percent	[1]	66.00%	69.00%
Multifamily [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Loans | MortgageLoan		8	5
Loans - principal (in Dollars) | $		$ 5,337,203	$ 2,164,861
Loans - percent		9.00%	4.00%
Commercial [Member]
Loans (Details) - Secured Loans by Property Type [Line Items]
Loans | MortgageLoan		20	21
Loans - principal (in Dollars) | $		$ 14,598,679	$ 14,988,612
Loans - percent		25.00%	27.00%

[1] Single family property type as of March 31, 2018 consists of 11 loans with principal of $6,506,239 that are owner occupied and 54 loans with principal of $31,423,270 that are non-owner occupied. At December 31, 2017, single family property consisted of 10 loans with principal of $6,309,036 that are owner occupied and 57 loans with principal of $31,306,180 that are non-owner occupied.