Segment Reporting Assets and Liabilities by Segment (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Total Assets	$ 17,071,895		$ 16,317,028
Liabilities	15,382,385		14,726,206
Total Equity	1,689,510	$ 1,637,616	1,590,822	$ 1,573,859	$ 1,553,156	$ 1,535,612
Investment Portfolio Segment
Segment Reporting Information [Line Items]
Total Assets	5,322,931		5,628,583
Liabilities	3,776,344		4,076,568
Total Equity	1,546,587		1,552,015
Longbridge Segment
Segment Reporting Information [Line Items]
Total Assets	11,521,278		10,493,971
Liabilities	11,290,194		10,270,289
Total Equity	231,084		223,682
Corporate Segment and Other Operating Segment
Segment Reporting Information [Line Items]
Total Assets	227,686		194,474
Liabilities	315,847		379,349
Total Equity	$ (88,161)		$ (184,875)