Notes Receivable - Components (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Notes receivable activities
Notes receivable loan loss reserve	$ (189)	$ (146)
Total	18,675	14,465
Mezzanine loan
Notes receivable activities
Mezzanine loan	11,816	8,445
Other loans
Notes receivable activities
Mezzanine loan	$ 7,048	$ 6,166

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant