Quarterly report pursuant to Section 13 or 15(d)

Lines of Credit, Mortgage Payable and Churchill Facility (Details)

Lines of Credit, Mortgage Payable and Churchill Facility (Details)					1 Months Ended	3 Months Ended	12 Months Ended
	Sep. 08, 2023 USD ($)	Mar. 02, 2023 USD ($)	Feb. 28, 2023 USD ($)	Jul. 21, 2021 USD ($)	Feb. 28, 2023 USD ($)	Mar. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($) loan	Dec. 31, 2021 USD ($)	Dec. 31, 2020	Dec. 31, 2022 USD ($)
Line of Credit, Mortgage Payable, and Churchill Facility
Spread on variable rate						7.01%	6.77%
Outstanding balance						$ 62,251,343	$ 61,792,330
Amount outstanding						288,401,750
Amortization schedule			20 years
Term of Federal Home Loan Bank of Boston Classic Advance Rate					5 years
Unpaid principal balance						$ 44,600,000	$ 50,600,000
Threshold asset coverage ratio						150.00%
Number of first line mortgage loans \| loan						12	14
Maximum borrowing capacity						$ 10,000,000
Percentage of asset coverage ratio						150.00%
Revolving Credit Facility
Line of Credit, Mortgage Payable, and Churchill Facility
Outstanding balance						$ 35,000,000.0
Wells Fargo Credit line
Line of Credit, Mortgage Payable, and Churchill Facility
Spread on variable rate									1.75%
Outstanding balance						27,300,000	$ 26,800,000
New Haven Bank Mortgage
Line of Credit, Mortgage Payable, and Churchill Facility
Principal Amount			$ 1,660,000		$ 1,660,000			$ 1,400,000
Amount outstanding										$ 750,000
Fixed annual rate			5.75%		5.75%					3.75%
Interest accrued period					60 months		72 months
Period for which only interest is payable								12 months
Amortization schedule							20 years
Term of Federal Home Loan Bank of Boston Classic Advance Rate							5 years
Unpaid principal balance							$ 750,000
New Haven Bank Mortgage \| Federal Home Loan Bank of Boston Classic Advance Rate
Line of Credit, Mortgage Payable, and Churchill Facility
Spread on variable rate					1.75%		2.60%
Master Repurchase Agreement
Line of Credit, Mortgage Payable, and Churchill Facility
Outstanding balance						$ 25,900,000	$ 26,461,098
Fixed annual rate				0.25%
Repurchase face amount				$ 200,000,000
Notes callable period				90 days
Threshold asset coverage ratio						150.00%
Percentage amount of repurchase obligation of unencumbered cash and cash equivalents						2.50%
Term of debt						180 days
Credit and Security Agreement with Needham Bank
Line of Credit, Mortgage Payable, and Churchill Facility
Fixed annual rate						8.25%
Credit and Security Agreement with Needham Bank \| Revolving Credit Facility
Line of Credit, Mortgage Payable, and Churchill Facility
Right to extend the term (in years)		1 year
Interest rate	4.50%
Maximum borrowing capacity	$ 65,000,000	$ 75,000,000
Amount of credit facility		$ 45,000,000
Credit and Security Agreement with Needham Bank \| Prime Rate \| Revolving Credit Facility
Line of Credit, Mortgage Payable, and Churchill Facility
Percentage reduced from prime rate for calculating annual interest rate	0.25%
Minimum
Line of Credit, Mortgage Payable, and Churchill Facility
Repayment of long-term loan						$ 47,000
Term of debt						1 year
Adjusted EBITDA coverage ratio						1.0
Minimum \| Master Repurchase Agreement
Line of Credit, Mortgage Payable, and Churchill Facility
Fixed annual rate				3.00%
Minimum \| Credit and Security Agreement with Needham Bank \| Revolving Credit Facility
Line of Credit, Mortgage Payable, and Churchill Facility
Notice period for terminating the Credit Facility, prior to the proposed date of termination		10 days
Maximum
Line of Credit, Mortgage Payable, and Churchill Facility
Repayment of long-term loan						$ 59,000
Term of debt						3 years
Adjusted EBITDA coverage ratio						1.40
Maximum \| Master Repurchase Agreement
Line of Credit, Mortgage Payable, and Churchill Facility
Fixed annual rate				4.00%