Fair Value - Narrative (Details)	3 Months Ended							9 Months Ended		12 Months Ended
	Sep. 30, 2025 USD ($) loan property	Jun. 30, 2025 USD ($) loan property	Mar. 31, 2025 USD ($) loan	Dec. 31, 2024 USD ($) loan property	Sep. 30, 2024 USD ($) forwardSwap	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2025 USD ($) loan property	Sep. 30, 2024 USD ($) forwardSwap	Dec. 31, 2024 USD ($) loan property
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve								$ 8,562,000	$ 115,313,000
Impairment of operating real estate	$ 2,509,000	$ 51,100,000			$ 0			$ 53,636,000	45,216,000
Number of impaired properties | property	1	2						1
Number of properties individually evaluated | property								2
Hotel Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans on nonaccrual collateral dependent | loan	1									1
Multifamily
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans on nonaccrual collateral dependent | loan		1
Impairment of operating real estate								$ 6,700,000
Number of legal titles acquired | property				1				1
Denver, Colorado
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve									$ (1,000,000)
Number of loans on nonaccrual status | loan	1	1		1				1		1
Hotel Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve	$ 17,900,000	$ 1,300,000
Number of loans on nonaccrual collateral dependent | loan										1
Multifamily
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve		18,200,000
Number of loans on nonaccrual status	1				2			1	2
Multifamily | Denver, Colorado
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans on nonaccrual status | loan	2							2
Multifamily loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve			$ 9,200,000	$ 9,000,000						$ 30,000,000
Number of loans on nonaccrual status | loan	1		1	2				1		2
Number of loans on nonaccrual collateral dependent | loan										1
Multifamily loans | Denver, Colorado
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve										$ 1,000,000
Office loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans on nonaccrual status	1			2	1			1	1	2
Number of loans on nonaccrual collateral dependent | loan										2
Number of loans on nonaccrual repayment | loan										1
Number of office properties held for sale | property										1
Industrial Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans on nonaccrual status | loan	1							1
Development Mezzanine Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans on nonaccrual status				1	1				1	1
Loans held for investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve	$ 17,891,000	$ 19,482,000	$ 9,174,000		$ 9,103,000	$ 11,791,000	$ 7,128,000
Number of loans on nonaccrual status | loan	1							1
Loans held for investment | Denver, Colorado
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Increase of current expected credit loss reserve								$ 46,500,000	$ (29,000,000)
Loans held for investment | Long Island City, New York
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of operating real estate										$ 47,500,000
Number of properties individually evaluated | property										3
Other real estate foreclosed assets				$ 6,700,000						$ 6,700,000
Discount Rate | Hotel Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	0.120	0.105						0.120
Discount Rate | Multifamily loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.060						0.060
Capitalization Rate | Hotel Loan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	0.085	0.080						0.085
Capitalization Rate | Multifamily loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.053						0.053
Other assets - PE Investments | Level 3 | Recurring basis | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	0.110							0.110
Minimum | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	0.100			0.095				0.100		0.095
Minimum | Discount Rate | Loans held for investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.081						0.081
Minimum | Capitalization Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	0.055			0.080				0.055		0.080
Minimum | Capitalization Rate | Loans held for investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.055						0.055
Minimum | Level 3 | Sales price
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input		42,823
Minimum | Other assets - PE Investments | Level 3 | Recurring basis | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.110						0.110
Maximum | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	0.179			0.202				0.179		0.202
Maximum | Discount Rate | Loans held for investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.098						0.098
Maximum | Capitalization Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	0.191			0.088				0.191		0.088
Maximum | Capitalization Rate | Loans held for investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.095						0.095
Maximum | Sales price
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input	97							97
Maximum | Level 3 | Sales price
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input		86,824
Maximum | Other assets - PE Investments | Level 3 | Recurring basis | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.120						0.120
Weighted average | Capitalization Rate | Loans held for investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input				0.076						0.076