Debt and Preferred Equity Investments - Rollforward of Total Allowance for Loan Loss Reserves (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Loan loss reserve activity
Balance at beginning of year	$ 6,630	$ 13,213	$ 1,750
Current period provision for loan loss	0	0	20,693
Write-offs charged against the allowance	0	(6,583)	(37,033)
Balance at end of year	$ 6,630	6,630	13,213
Number of financing receivables on non-accrual without allowance for loan loss \| loan	1
Financing receivable on non-accrual without allowance	$ 225,400
Cumulative Effect, Period of Adoption, Adjustment
Loan loss reserve activity
Balance at beginning of year	$ 0	0	27,803
Balance at end of year		$ 0	$ 0

Financing Receivable, Nonaccrual, No Allowance, Number

No definition available.

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=123605502&loc=d3e21338-158488

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

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Balance Type:	debit
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- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

+ Details

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- Details

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