v3.26.3
Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Income Tax Disclosure [Abstract]        
GAAP net income (loss) $ (323,746) $ 159,259 $ (263,781) $ 110,983
Book to tax differences:        
ARMOUR TRS Inc. (income) loss 64 (94) (18) (289)
Gain (Loss) on Agency Securities, trading, net 1,165,185 (177,108) 1,390,404 (401,910)
Gain (Loss) on U.S. Treasury Securities, net 18,227 (6,197) 39,329 9,596
Changes in interest rate contracts (757,419) 101,641 (875,489) 491,547
Amortization of deferred hedging costs (13,914) (18,437) (48,718) (52,132)
Amortization of deferred Treasury Future gains 2,881 1,981 3,167 7,558
Other 838 113 945 242
Estimated REIT taxable income $ 92,116 $ 61,158 $ 245,839 $ 165,595