INVESTMENT SECURITIES - Schedule of Farmer Mac Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
AFS Securities
Amortized Cost	$ 15,249,174	$ 13,813,551
AFS investment securities	14,891,506	13,580,285
HTM:
Amortized cost	4,514,893	3,954,223
Total AFS Investment Securities
AFS Securities
Amortized Cost	15,249,174	13,813,551
Allowance for losses	(79)	(130)
Unrealized Gains	21,467	71,380
Unrealized Losses	(379,056)	(304,516)
AFS investment securities	14,891,506	13,580,285
HTM:
Amortized cost	4,514,995	3,954,300
Allowance for losses	(102)	(77)
Unrealized Gains	21,003	22,576
Unrealized Losses	(207,582)	(182,847)
Total	4,328,314	3,793,952
Available-for-sale, accrued interest excluded	98,900	91,300
Held-to-maturity, accrued interest excluded	47,500	56,700
Government/GSE guaranteed MBS
AFS Securities
Amortized Cost	5,708,315	5,351,174
Allowance for losses	0	0
Unrealized Gains	14,159	35,078
Unrealized Losses	(105,596)	(89,234)
AFS investment securities	5,616,878	5,297,018
HTM:
Amortized cost	8,329	8,657
Allowance for losses	0	0
Unrealized Gains	177	281
Unrealized Losses	0	0
Total	8,506	8,938
U.S. Treasuries
AFS Securities
Amortized Cost	1,503,673	1,537,112
Allowance for losses	0	0
Unrealized Gains	277	7,083
Unrealized Losses	(5,891)	(48)
AFS investment securities	1,498,059	1,544,147
ABS
AFS Securities
Amortized Cost	65,320
Allowance for losses	0
Unrealized Gains	154
Unrealized Losses	0
AFS investment securities	65,474
AgVantage
AFS Securities
Amortized Cost	7,964,127	6,917,225
Allowance for losses	(79)	(130)
Unrealized Gains	6,490	29,056
Unrealized Losses	(267,569)	(215,234)
AFS investment securities	7,702,969	6,730,917
HTM:
Amortized cost	1,961,033	1,486,284
Allowance for losses	(102)	(77)
Unrealized Gains	18,008	16,444
Unrealized Losses	(12,197)	(3,731)
Total	1,966,742	1,498,920
Interest-Only Farmer Mac Guaranteed Securities
AFS Securities
Amortized Cost	7,739	8,040
Allowance for losses	0	0
Unrealized Gains	387	163
Unrealized Losses	0	0
AFS investment securities	8,126	8,203
USDA Securities
HTM:
Amortized cost	2,545,633	2,459,359
Allowance for losses	0	0
Unrealized Gains	2,818	5,851
Unrealized Losses	(195,385)	(179,116)
Total	$ 2,353,066	$ 2,286,094

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