Loans - Secured Loans by Lien Position in the Collateral (Details)		1 Months Ended	12 Months Ended
		Mar. 31, 2022 USD ($) MortgageLoan	Dec. 31, 2021 USD ($) MortgageLoan	Dec. 31, 2020 USD ($) MortgageLoan	Dec. 31, 2019 USD ($)
Loans (Details) - Secured Loans by Lien Position in the Collateral [Line Items]
Number of secured loans | MortgageLoan		1	54	82
Principal		$ 586,000	$ 81,097,000	$ 82,275,000	$ 70,660,000
Liens due other lenders at loan closing			31,338,000	45,207,000
Total debt			112,435,000	127,482,000
Appraised property value at loan closing			$ 215,683,000	$ 251,970,000
Percent of total debt to appraised values (LTV) at loan closing	[1]		58.00%	55.60%
Loans - percent			100.00%	100.00%
First Trust Deeds [Member]
Loans (Details) - Secured Loans by Lien Position in the Collateral [Line Items]
Number of secured loans | MortgageLoan			38	56
Principal			$ 69,327,000	$ 61,066,000
Loans - percent			85.00%	74.00%
Second Trust Deeds [Member]
Loans (Details) - Secured Loans by Lien Position in the Collateral [Line Items]
Number of secured loans | MortgageLoan			16	26
Principal			$ 11,770,000	$ 21,209,000
Loans - percent			15.00%	26.00%

[1] Based on appraised values and liens due to other lenders at loan closing. The weighted-average loan-to-value (LTV) computation above does not take into account subsequent increases or decreases in property values following the loan closing nor does it include decreases or increases of the amount of senior liens to other lenders.