INVESTMENT SECURITIES - Schedule of Farmer Mac Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
AFS Securities
Amortized Cost	$ 14,269,843	$ 13,813,551
AFS investment securities	13,971,122	13,580,285
HTM:
Amortized cost	4,230,583	3,954,223
Total AFS Investment Securities
AFS Securities
Amortized Cost	14,269,843	13,813,551
Allowance for losses	(138)	(130)
Unrealized Gains	41,921	71,380
Unrealized Losses	(340,504)	(304,516)
AFS investment securities	13,971,122	13,580,285
HTM:
Amortized cost	4,230,652	3,954,300
Allowance for losses	(69)	(77)
Unrealized Gains	16,223	22,576
Unrealized Losses	(190,937)	(182,847)
Total	4,055,869	3,793,952
Available-for-sale, accrued interest excluded	98,100	91,300
Held-to-maturity, accrued interest excluded	45,100	56,700
Government/GSE guaranteed MBS
AFS Securities
Amortized Cost	5,549,969	5,351,174
Allowance for losses	0	0
Unrealized Gains	22,954	35,078
Unrealized Losses	(96,089)	(89,234)
AFS investment securities	5,476,834	5,297,018
HTM:
Amortized cost	8,497	8,657
Allowance for losses	0	0
Unrealized Gains	204	281
Unrealized Losses	0	0
Total	8,701	8,938
U.S. Treasuries
AFS Securities
Amortized Cost	1,612,868	1,537,112
Allowance for losses	0	0
Unrealized Gains	2,338	7,083
Unrealized Losses	(2,416)	(48)
AFS investment securities	1,612,790	1,544,147
ABS
AFS Securities
Amortized Cost	45,000
Allowance for losses	0
Unrealized Gains	0
Unrealized Losses	(414)
AFS investment securities	44,586
AgVantage
AFS Securities
Amortized Cost	7,054,127	6,917,225
Allowance for losses	(138)	(130)
Unrealized Gains	16,355	29,056
Unrealized Losses	(241,585)	(215,234)
AFS investment securities	6,828,759	6,730,917
HTM:
Amortized cost	1,723,852	1,486,284
Allowance for losses	(69)	(77)
Unrealized Gains	11,616	16,444
Unrealized Losses	(10,897)	(3,731)
Total	1,724,502	1,498,920
Interest-Only Farmer Mac Guaranteed Securities
AFS Securities
Amortized Cost	7,879	8,040
Allowance for losses	0	0
Unrealized Gains	274	163
Unrealized Losses	0	0
AFS investment securities	8,153	8,203
USDA Securities
HTM:
Amortized cost	2,498,303	2,459,359
Allowance for losses	0	0
Unrealized Gains	4,403	5,851
Unrealized Losses	(180,040)	(179,116)
Total	$ 2,322,666	$ 2,286,094

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