Farmer Mac Guaranteed Securities and USDA Securities - Schedule of On-Balance Sheet Securities (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	$ 1,328,121,000	$ 2,033,345,000
Amortized Cost	1,328,095,000	2,033,371,000
Allowance for losses	(56,000)	(132,000)
Unrealized Gains	1,000	11,259,000
Unrealized Losses	(62,428,000)	(12,764,000)
Fair Value	1,265,612,000	2,031,734,000
Available-for-sale:
Amortized cost	7,421,595,000
Fair Value	6,974,002,000
USDA Securities:
Held-to-maturity:
Unpaid Principal Balance	2,404,124,000	2,411,649,000
Amortized Cost	2,428,638,000	2,436,331,000
Allowance for losses	0	0
Unrealized Gains	178,000	95,741,000
Unrealized Losses	(398,119,000)	0
Fair Value	2,030,697,000	2,532,072,000
Trading:
Unpaid Principal Balance	1,879,000	4,299,000
Amortized Cost	1,958,000	4,433,000
Allowance for losses	0	0
Unrealized Gains	0	1,000
Unrealized Losses	(107,000)	(33,000)
Fair Value	1,851,000	$ 4,401,000
Trading securities, weighted-average yield		5.05%
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	3,732,245,000	$ 4,444,994,000
Amortized Cost	3,756,733,000	4,469,702,000
Allowance for losses	(56,000)	(132,000)
Unrealized Gains	179,000	107,000,000
Unrealized Losses	(460,547,000)	(12,764,000)
Fair Value	3,296,309,000	4,563,806,000
Farmer Mac Guaranteed Securities:
Held-to-maturity:
Amortized Cost	1,328,039,000	2,033,239,000
Available-for-sale:
Unpaid Principal Balance	7,409,650,000	6,122,240,000
Amortized cost	7,421,595,000	6,135,807,000
Allowance for losses	(608,000)	(263,000)
Unrealized Gains	1,946,000	213,025,000
Unrealized Losses	(448,931,000)	(20,010,000)
Fair Value	6,974,002,000	6,328,559,000
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(26,000)	26,000
Available-for-sale:
Unamortized Premium/(Discount)	(26,000)	26,000
Trading:
Unamortized Premium/(Discount)	(26,000)	26,000
Held-to-Maturity Securities \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	24,514,000	24,682,000
Available-for-sale:
Unamortized Premium/(Discount)	24,514,000	24,682,000
Trading:
Unamortized Premium/(Discount)	24,514,000	24,682,000
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,488,000	24,708,000
Available-for-sale:
Unamortized Premium/(Discount)	24,488,000	24,708,000
Trading:
Unamortized Premium/(Discount)	24,488,000	24,708,000
Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	11,945,000	13,567,000
Available-for-sale:
Unamortized Premium/(Discount)	11,945,000	13,567,000
Trading:
Unamortized Premium/(Discount)	11,945,000	13,567,000
Debt Securities, Trading \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	79,000	134,000
Available-for-sale:
Unamortized Premium/(Discount)	79,000	134,000
Trading:
Unamortized Premium/(Discount)	79,000	134,000
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Fair Value	8,200,000	12,400,000
Trading:
Derivative, notional amount	251,600,000	275,400,000
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	0	0
Amortized cost	11,092,000	12,297,000
Allowance for losses	0	0
Unrealized Gains	0	117,000
Unrealized Losses	(2,851,000)	0
Fair Value	8,241,000	12,414,000
Farmer Mac Guaranteed Securities \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	11,092,000	12,297,000
Available-for-sale:
Unamortized Premium/(Discount)	11,092,000	12,297,000
Trading:
Unamortized Premium/(Discount)	11,092,000	12,297,000
AgVantage
Trading:
Available-for-sale, accrued interest excluded	44,000,000	29,800,000
Held-to-maturity, accrued interest excluded	41,100,000	42,100,000
Trading securities, accrued interest excluded	38,000	100,000
AgVantage \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	1,306,865,000	2,003,486,000
Amortized Cost	1,306,865,000	2,003,486,000
Allowance for losses	(56,000)	(132,000)
Unrealized Gains	0	10,097,000
Unrealized Losses	(60,668,000)	(12,764,000)
Fair Value	1,246,141,000	2,000,687,000
AgVantage \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	7,409,650,000	6,122,240,000
Amortized cost	7,410,503,000	6,123,510,000
Allowance for losses	(608,000)	(263,000)
Unrealized Gains	1,946,000	212,908,000
Unrealized Losses	(446,080,000)	(20,010,000)
Fair Value	6,965,761,000	6,316,145,000
AgVantage \| Held-to-Maturity 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
AgVantage \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	853,000	1,270,000
Available-for-sale:
Unamortized Premium/(Discount)	853,000	1,270,000
Trading:
Unamortized Premium/(Discount)	853,000	1,270,000
Farmer Mac Guaranteed USDA Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	21,256,000	29,859,000
Amortized Cost	21,230,000	29,885,000
Allowance for losses	0	0
Unrealized Gains	1,000	1,162,000
Unrealized Losses	(1,760,000)	0
Fair Value	$ 19,471,000	31,047,000
Farmer Mac Guaranteed USDA Securities \| USDA Securities:
Trading:
Trading securities, weighted-average yield	4.84%
Farmer Mac Guaranteed USDA Securities \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	$ (26,000)	26,000
Available-for-sale:
Unamortized Premium/(Discount)	(26,000)	26,000
Trading:
Unamortized Premium/(Discount)	$ (26,000)	$ 26,000

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