Farmer Mac Guaranteed Securities and USDA Securities - Schedule of On-Balance Sheet Securities (Details) - USD ($)		3 Months Ended
Dec. 31, 2022	Mar. 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 $9,885 and $12,514, respectively, related to consolidated trusts)	Accrued interest receivable (includes $9,885 and $12,514, respectively, related to consolidated trusts)
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	$ 1,021,275,000	$ 994,078,000
Amortized Cost	1,021,213,000	994,023,000
Allowance for losses	(59,000)	(57,000)
Unrealized Gains	355,000	459,000
Unrealized Losses	(54,954,000)	(44,668,000)
Fair Value	966,555,000	949,757,000
Available-for-sale:
Amortized cost		8,565,328,000
Fair Value		8,225,454,000
USDA Securities:
Held-to-maturity:
Unpaid Principal Balance	2,384,946,000	2,334,923,000
Amortized Cost	2,409,834,000	2,358,928,000
Allowance for losses	0	0
Unrealized Gains	668,000	475,000
Unrealized Losses	(312,824,000)	(216,826,000)
Fair Value	2,097,678,000	2,142,577,000
Trading:
Unpaid Principal Balance	1,770,000	1,391,000
Amortized Cost	1,850,000	1,463,000
Allowance for losses	0	0
Unrealized Gains	0	0
Unrealized Losses	(83,000)	(58,000)
Fair Value	$ 1,767,000	1,405,000
Trading securities, weighted-average yield	4.84%
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	$ 3,406,221,000	3,329,001,000
Amortized Cost	3,431,047,000	3,352,951,000
Allowance for losses	(59,000)	(57,000)
Unrealized Gains	1,023,000	934,000
Unrealized Losses	(367,778,000)	(261,494,000)
Fair Value	3,064,233,000	3,092,334,000
Farmer Mac Guaranteed Securities:
Held-to-maturity:
Amortized Cost	1,021,154,000	993,966,000
Available-for-sale:
Unpaid Principal Balance	8,008,067,000	8,554,373,000
Amortized cost	8,019,495,000	8,565,328,000
Allowance for losses	(546,000)	(515,000)
Unrealized Gains	2,061,000	7,296,000
Unrealized Losses	(413,784,000)	(346,655,000)
Fair Value	7,607,226,000	8,225,454,000
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(62,000)	(55,000)
Available-for-sale:
Unamortized Premium/(Discount)	(62,000)	(55,000)
Trading:
Unamortized Premium/(Discount)	(62,000)	(55,000)
Held-to-Maturity Securities \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	24,888,000	24,005,000
Available-for-sale:
Unamortized Premium/(Discount)	24,888,000	24,005,000
Trading:
Unamortized Premium/(Discount)	24,888,000	24,005,000
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,826,000	23,950,000
Available-for-sale:
Unamortized Premium/(Discount)	24,826,000	23,950,000
Trading:
Unamortized Premium/(Discount)	24,826,000	23,950,000
Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	11,428,000	10,955,000
Available-for-sale:
Unamortized Premium/(Discount)	11,428,000	10,955,000
Trading:
Unamortized Premium/(Discount)	11,428,000	10,955,000
Debt Securities, Trading \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	80,000	72,000
Available-for-sale:
Unamortized Premium/(Discount)	80,000	72,000
Trading:
Unamortized Premium/(Discount)	80,000	72,000
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Fair Value	7,800,000	8,000,000
Trading:
Derivative, notional amount	250,100,000	244,600,000
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	0	0
Amortized cost	10,622,000	10,189,000
Allowance for losses	0	0
Unrealized Gains	0	0
Unrealized Losses	(2,775,000)	(2,155,000)
Fair Value	7,847,000	8,034,000
Farmer Mac Guaranteed Securities \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	10,622,000	10,189,000
Available-for-sale:
Unamortized Premium/(Discount)	10,622,000	10,189,000
Trading:
Unamortized Premium/(Discount)	10,622,000	10,189,000
AgVantage
Trading:
Available-for-sale, accrued interest excluded	51,500,000	63,600,000
Held-to-maturity, accrued interest excluded	44,400,000	36,900,000
Trading securities, accrued interest excluded	47,000	27,000
AgVantage \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	1,000,689,000	973,697,000
Amortized Cost	1,000,594,000	973,610,000
Allowance for losses	(59,000)	(57,000)
Unrealized Gains	353,000	445,000
Unrealized Losses	(54,098,000)	(43,839,000)
Fair Value	946,790,000	930,159,000
AgVantage \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	8,008,067,000	8,554,373,000
Amortized cost	8,008,873,000	8,555,139,000
Allowance for losses	(546,000)	(515,000)
Unrealized Gains	2,061,000	7,296,000
Unrealized Losses	(411,009,000)	(344,500,000)
Fair Value	7,599,379,000	8,217,420,000
AgVantage \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(95,000)	(87,000)
Available-for-sale:
Unamortized Premium/(Discount)	(95,000)	(87,000)
Trading:
Unamortized Premium/(Discount)	(95,000)	(87,000)
AgVantage \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	806,000	766,000
Available-for-sale:
Unamortized Premium/(Discount)	806,000	766,000
Trading:
Unamortized Premium/(Discount)	806,000	766,000
Farmer Mac Guaranteed USDA Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	20,586,000	20,381,000
Amortized Cost	20,619,000	20,413,000
Allowance for losses	0	0
Unrealized Gains	2,000	14,000
Unrealized Losses	(856,000)	(829,000)
Fair Value	19,765,000	$ 19,598,000
Farmer Mac Guaranteed USDA Securities \| USDA Securities:
Trading:
Trading securities, weighted-average yield		5.52%
Farmer Mac Guaranteed USDA Securities \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	33,000	$ 32,000
Available-for-sale:
Unamortized Premium/(Discount)	33,000	32,000
Trading:
Unamortized Premium/(Discount)	$ 33,000	$ 32,000

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