Real Estate Securities - Components of Carrying Value of Residential Available for Sale Securities in Unrealized Loss Position (Details) - Residential - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Consecutive Months, Fair Value	$ 9,459	$ 72,679
Less Than 12 Consecutive Months, Unrealized Losses	(585)	(12,940)
12 Consecutive Months or Longer, Fair Value	28,630	1,414
12 Consecutive Months or Longer, Unrealized Losses	$ (8,399)	$ (186)