Loans - Secured Loans Scheduled Maturities (Details)	Dec. 31, 2021 USD ($) Loan	Dec. 31, 2020 USD ($) Loan	Dec. 31, 2019 USD ($)
Receivables [Abstract]
2022, Loan | Loan	17
2023, Loan | Loan	6
2024, Loan | Loan	1
2025, Loan | Loan	1
2026, Loan | Loan	0
Thereafter, Loan | Loan	2
Total scheduled maturities, Loan | Loan	27
Matured at December 31, 2021, Loan | Loan	4
Total principal, secured loans, Loan | Loan	31	33
2022, Principal | $	$ 45,108,000
2023, Principal | $	6,049,000
2024, Principal | $	588,000
2025, Principal | $	1,000,000
2026, Principal | $	0
Thereafter, Principal | $	1,310,000
Total scheduled maturities, Principal | $	54,055,000
Matured at December 31, 2021, Principal | $	1,044,000
Total principal, secured loans, Principal | $	$ 55,099,000	$ 74,080,000	$ 86,203,000
2022, Percent	82.00%
2023, Percent	11.00%
2024, Percent	1.00%
2025, Percent	2.00%
2026, Percent	0.00%
Thereafter, Percent	2.00%
Total scheduled maturities, Percent	98.00%
Matured at December 31, 2021, Percent	2.00%
Total principal, secured loans, Percent	100.00%