FARMER MAC GUARANTEED SECURITIES AND USDA SECURITIES - Schedule of On-Balance Sheet Securities (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Trading:
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Accrued interest receivable (includes $9,963 and $16,764, respectively, related to consolidated trusts)	Accrued interest receivable (includes $9,963 and $16,764, respectively, related to consolidated trusts)
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	$ 4,483,971,000	$ 4,242,867,000
Amortized Cost	4,455,111,000	4,213,278,000
Allowance for losses	(179,000)	(209,000)
Unrealized Gains	3,888,000	4,783,000
Unrealized Losses	(36,013,000)	(40,257,000)
Fair Value	4,422,807,000	4,177,595,000
Available-for-sale:
Amortized cost	5,811,302,000
Fair Value	5,466,688,000
USDA Securities
Held-to-maturity:
Unpaid Principal Balance	2,311,442,000	2,331,093,000
Amortized Cost	2,333,027,000	2,354,171,000
Allowance for losses	0	0
Unrealized Gains	303,000	417,000
Unrealized Losses	(318,319,000)	(319,783,000)
Fair Value	2,015,011,000	2,034,805,000
Trading:
Unpaid Principal Balance	1,069,000	1,236,000
Amortized Cost	1,126,000	1,300,000
Allowance for losses	0	0
Unrealized Gains	0	0
Unrealized Losses	(60,000)	(59,000)
Fair Value	1,066,000	$ 1,241,000
Trading securities, weighted-average yield		5.46%
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	6,795,413,000	$ 6,573,960,000
Amortized Cost	6,788,138,000	6,567,449,000
Allowance for losses	(179,000)	(209,000)
Unrealized Gains	4,191,000	5,200,000
Unrealized Losses	(354,332,000)	(360,040,000)
Fair Value	6,437,818,000	6,212,400,000
Farmer Mac Guaranteed Securities
Held-to-maturity:
Amortized Cost	4,454,932,000	4,213,069,000
Available-for-sale:
Unpaid Principal Balance	5,802,070,000	5,816,024,000
Amortized cost	5,811,302,000	5,825,433,000
Allowance for losses	(291,000)	(317,000)
Unrealized Gains	8,623,000	16,774,000
Unrealized Losses	(352,946,000)	(309,411,000)
Fair Value	5,466,688,000	5,532,479,000
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(28,860,000)	(29,589,000)
Available-for-sale:
Unamortized Premium/(Discount)	(28,860,000)	(29,589,000)
Trading:
Unamortized Premium/(Discount)	(28,860,000)	(29,589,000)
Held-to-Maturity Securities \| USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	21,585,000	23,078,000
Available-for-sale:
Unamortized Premium/(Discount)	21,585,000	23,078,000
Trading:
Unamortized Premium/(Discount)	21,585,000	23,078,000
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(7,275,000)	(6,511,000)
Available-for-sale:
Unamortized Premium/(Discount)	(7,275,000)	(6,511,000)
Trading:
Unamortized Premium/(Discount)	(7,275,000)	(6,511,000)
Available-for-Sale Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	9,232,000	9,409,000
Available-for-sale:
Unamortized Premium/(Discount)	9,232,000	9,409,000
Trading:
Unamortized Premium/(Discount)	9,232,000	9,409,000
Trading Securities \| USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	57,000	64,000
Available-for-sale:
Unamortized Premium/(Discount)	57,000	64,000
Trading:
Unamortized Premium/(Discount)	57,000	64,000
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Fair Value	9,500,000	9,800,000
Trading:
Derivative, notional amount	233,500,000	238,400,000
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Unpaid Principal Balance	0	0
Amortized cost	9,232,000	9,409,000
Allowance for losses	0	0
Unrealized Gains	259,000	358,000
Unrealized Losses	0	0
Fair Value	9,491,000	9,767,000
Farmer Mac Guaranteed Securities \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	9,232,000	9,409,000
Available-for-sale:
Unamortized Premium/(Discount)	9,232,000	9,409,000
Trading:
Unamortized Premium/(Discount)	9,232,000	9,409,000
AgVantage
Trading:
Available-for-sale, accrued interest excluded	57,900,000	47,200,000
Held-to-maturity, accrued interest excluded	59,400,000	67,400,000
Trading securities, accrued interest excluded	27,610	42,000
AgVantage \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	4,441,588,000	4,206,324,000
Amortized Cost	4,412,697,000	4,176,702,000
Allowance for losses	(179,000)	(209,000)
Unrealized Gains	3,829,000	4,676,000
Unrealized Losses	(35,130,000)	(39,451,000)
Fair Value	4,381,217,000	4,141,718,000
AgVantage \| Farmer Mac Guaranteed Securities
Available-for-sale:
Unpaid Principal Balance	5,802,070,000	5,816,024,000
Amortized cost	5,802,070,000	5,816,024,000
Allowance for losses	(291,000)	(317,000)
Unrealized Gains	8,364,000	16,416,000
Unrealized Losses	(352,946,000)	(309,411,000)
Fair Value	5,457,197,000	5,522,712,000
AgVantage \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(28,891,000)	(29,622,000)
Available-for-sale:
Unamortized Premium/(Discount)	(28,891,000)	(29,622,000)
Trading:
Unamortized Premium/(Discount)	(28,891,000)	(29,622,000)
AgVantage \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	0	0
Available-for-sale:
Unamortized Premium/(Discount)	0	0
Trading:
Unamortized Premium/(Discount)	0	0
Farmer Mac Guaranteed USDA Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	42,383,000	36,543,000
Amortized Cost	42,414,000	36,576,000
Allowance for losses	0	0
Unrealized Gains	59,000	107,000
Unrealized Losses	(883,000)	(806,000)
Fair Value	$ 41,590,000	35,877,000
Farmer Mac Guaranteed USDA Securities \| USDA Securities
Trading:
Trading securities, weighted-average yield	5.58%
Farmer Mac Guaranteed USDA Securities \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	$ 31,000	33,000
Available-for-sale:
Unamortized Premium/(Discount)	31,000	33,000
Trading:
Unamortized Premium/(Discount)	$ 31,000	$ 33,000

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