Related-Party Transactions - Investments in Loans and Securities (Details) $ in Thousands	1 Months Ended					3 Months Ended	12 Months Ended
	Jan. 31, 2025 USD ($) unit	Dec. 31, 2024 USD ($) shares	May 31, 2024 USD ($) extension	Jul. 31, 2023	Dec. 31, 2012 USD ($) shares	Mar. 31, 2025 USD ($) transaction shares	Dec. 31, 2012 USD ($) shares	Jul. 31, 2024 USD ($) mortgageLoan	Mar. 31, 2022 USD ($)
Related-Party Transactions
Number of related-party loan transactions | transaction						3
Carrying Value		$ 18,401,316				$ 19,396,682
Loans held-for-investment		$ 15,437,013				$ 16,521,979
Weighted-average Spread Above Index						3.60%
SEREF
Related-Party Transactions
Number of shares acquired (in shares) | shares							9,140,000
Remaining held (in shares) | shares		4,480,649				3,420,384
Number of shares redeemed (in shares) | shares						1,060,265
Proceeds from shares redeemed						$ 1,400
Ownership percentage						2.30%
Affiliated Entity | SEREF
Related-Party Transactions
Number of shares acquired (in shares) | shares					9,140,000
Investment securities value at acquisition					$ 14,700		$ 14,700
Investment in equity securities percentage ownership acquired					4.00%
Remaining held (in shares) | shares		4,480,649				3,420,384
Number of shares redeemed (in shares) | shares						1,060,265
Proceeds from shares redeemed						$ 1,400
Ownership percentage						2.30%
Construction of Luxury Condominium Project | Affiliated Entity | Affiliates Of Manager | Borrower
Related-Party Transactions
Limited partnership interest	90.00%
Construction of Luxury Condominium Project | Affiliated Entity | Loans Payable
Related-Party Transactions
Percentage of origination of loan	49.00%
Face Amount	$ 388,400
Number of units | unit	81
Amount funded	$ 61,100
Initial term	4 years
Loan extension term	1 year
Floor interest rate (as a percent)	3.00%
Pricing margin (as a percent)	4.25%
Percentage of loan originated by third party	51.00%
Construction of Luxury Condominium Project | Affiliated Entity | Loans Payable | Starwood Property Trust Inc
Related-Party Transactions
Face Amount	$ 190,300
Development and Recapitalization of Luxury Rental Cabins | Affiliated Entity
Related-Party Transactions
Loan extension term		24 months
Conditional extension term		1 year
Decrease in interest rate		2.25%
Loans payable, basis spread		4.25%
Loan payable, payment deferral term				10 months
Loan payable, payment deferral interest rate				3.00%
Loans payable						$ 147,800
Loans payable, payment deferral, interest						$ 14,100
Development and Recapitalization of Luxury Rental Cabins | Affiliated Entity | Loans Payable
Related-Party Transactions
Face Amount		$ 25,000							$ 200,000
Refinancing of Medical Office Portfolio | Affiliated Entity
Related-Party Transactions
Loan extension term			1 year
Loans payable, basis spread			5.50%
Loan number of extension options | extension			3
Refinancing of Medical Office Portfolio | Affiliated Entity | Horizontal Risk Retention Certificates
Related-Party Transactions
Face Amount			$ 23,000
Refinancing of Medical Office Portfolio | Affiliated Entity | Loans Payable
Related-Party Transactions
Face Amount			$ 39,500
Initial term			2 years
Refinancing of Medical Office Portfolio | Affiliated Entity | Secured Borrowings | MED 2024-MOB
Related-Party Transactions
Face Amount			$ 450,500
Primary Beneficiary | Purchase Of FREMF 2024-KF163 | Affiliated Entity
Related-Party Transactions
Loans held-for-investment								$ 77,100
Weighted-average Spread Above Index								6.00%
Primary Beneficiary | Newly Formed FREMF 2024-KF163 Trust | Affiliated Entity
Related-Party Transactions
Loans held-for-investment								$ 1,000,000
Number of mortgage loans | mortgageLoan								26
Primary Beneficiary | Newly Formed FREMF 2024-KF163 Trust | Affiliates Of Manager
Related-Party Transactions
Loans held-for-investment								$ 495,000
Number of mortgage loans | mortgageLoan								11