GOVERNMENT AND GOVERNMENT-BACKED SECURITIES - Schedule of Investment in Real Estate Securities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Treasury
Purchases:
Face	$ 25,000	$ 5,775,000	$ 75,000	$ 8,800,000
Purchase price	24,755	5,787,401	74,222	8,788,328
Sales:
Face	1,250,000	2,500,000	3,250,000	5,500,000
Amortized cost	1,254,648	2,505,430	3,257,383	5,481,688
Sale price	1,255,371	2,542,051	3,269,180	5,499,395
Gain (loss) on sale	723	36,621	11,797	17,707
Agency
Purchases:
Face	1,034,285	0	2,390,086	1,280,545
Purchase price	1,030,943	0	2,357,838	1,249,562
Sales:
Face	0	2,556,839	1,274	2,556,839
Amortized cost	0	2,536,357	1,349	2,536,357
Sale price	0	2,583,782	1,291	2,583,782
Gain (loss) on sale	$ 0	$ 47,425	$ (58)	$ 47,425