Loans Held for Investment, net - Loan Risk Ratings Carrying Value (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	25	27
Percentage of Portfolio	100.00%	100.00%
Year one	$ 0	$ 206,022
Year two	207,168	340,818
Year three	308,164	78,448
Prior	106,738	44,641
Loans held for investment	$ 622,070	$ 669,929
1
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	1	1
Percentage of Portfolio	2.00%	1.00%
Year one	$ 0	$ 0
Year two	0	0
Year three	0	9,708
Prior	9,496	0
Loans held for investment	$ 9,496	$ 9,708
2
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	5	6
Percentage of Portfolio	20.00%	20.00%
Year one	$ 0	$ 0
Year two	41,952	65,902
Year three	31,483	68,740
Prior	52,289	0
Loans held for investment	$ 125,724	$ 134,642
3
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	16	17
Percentage of Portfolio	63.00%	65.00%
Year one	$ 0	$ 169,516
Year two	128,678	235,602
Year three	236,711	0
Prior	29,001	28,998
Loans held for investment	$ 394,390	$ 434,116
4
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	3	3
Percentage of Portfolio	15.00%	14.00%
Year one	$ 0	$ 36,506
Year two	36,538	39,314
Year three	39,970	0
Prior	15,952	15,643
Loans held for investment	$ 92,460	$ 91,463
5
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	0	0
Percentage of Portfolio	0.00%	0.00%
Year one	$ 0	$ 0
Year two	0	0
Year three	0	0
Prior	0	0
Loans held for investment	$ 0	$ 0

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Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Footnote 3
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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated in current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated two years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest of financing receivable originated in fiscal year prior to current fiscal year. Excludes net investment in lease.

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