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Agreements and Transactions with Related Parties - Other Related Party (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2025 USD ($) entity shares	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) entity shares	Jun. 30, 2024 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) loan property	Dec. 31, 2024 USD ($)
Agreements and Transactions with Related Parties
Due from related party	$ 16,773		$ 16,773					$ 12,792
Due to related party	3,396		3,396					$ 4,474
Other Related Party Transactions \| Related Party
Agreements and Transactions with Related Parties
Reimbursement for flights chartered by the company's executives	$ 700	$ 300	$ 900	$ 300
Other Related Party Transactions \| Related Party \| ACM Acquisition \| ACM
Agreements and Transactions with Related Parties
Number of shares held by related party (in shares) \| shares	2,535,870		2,535,870
Number of operating units held by related party (in shares) \| shares			10,483,930
Aggregate percentage of voting power held by related party	6.20%		6.20%
Other Related Party Transactions \| Related Party \| Maturity Date Of June 2021 \| Bridge loans
Agreements and Transactions with Related Parties
Number of bridge loans originated \| loan							12
Principal amount							$ 280,500
Number of multifamily properties renovated \| property							72
Other Related Party Transactions \| Related Party \| Maturity date of March 2030 \| Private Label \| Lexford Portfolio
Agreements and Transactions with Related Parties
Fixed rate of interest					3.30%
Other Related Party Transactions \| Related Party \| Maturity date December 2029 \| Bridge loans \| Lexford Portfolio
Agreements and Transactions with Related Parties
Maximum exposure under guaranty	$ 400,000		$ 400,000
Other Related Party Transactions \| Chief executive officer
Agreements and Transactions with Related Parties
Percentage of our former manager's outstanding membership interest of related party in another related party	35.00%		35.00%
Other Related Party Transactions \| Chief executive officer \| Minimum
Agreements and Transactions with Related Parties
Ownership percentage limit of our common stock under company charter	5.00%		5.00%
Other Related Party Transactions \| Director
Agreements and Transactions with Related Parties
Number of Kaufman entities \| entity	2		2
Lexford Portfolio
Agreements and Transactions with Related Parties
Distribution received	$ 3,400	4,200	$ 3,400	4,200
Lexford Portfolio \| Other Related Party Transactions \| Related Party
Agreements and Transactions with Related Parties
Management fee, percentage of gross revenues of underlying properties			4.75%
Lexford Portfolio \| Other Related Party Transactions \| Related Party \| Maturity Date Of June 2021 \| Bridge loans
Agreements and Transactions with Related Parties
Base spread, percentage							4.00%
Payoffs and partial paydowns of principal						$ 250,000
Unsecured financing provided by an unsecured lender to certain parent entities of the property owners							$ 50,000
Distribution received	$ 3,400	$ 4,200	$ 3,400	$ 4,200
Lexford Portfolio \| Other Related Party Transactions \| Related Party \| Maturity date of March 2030 \| Private Label
Agreements and Transactions with Related Parties
Principal amount					$ 34,600