Farmer Mac Guaranteed Securities and USDA Securities - Schedule of On-Balance Sheet Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	$ 1,906,421	$ 2,033,345
Amortized Cost	1,906,378	2,033,371
Allowance for losses	(160)	(132)
Unrealized Gains	3,144	11,259
Unrealized Losses	(33,541)	(12,764)
Fair Value	1,875,821	2,031,734
Available-for-sale:
Amortized cost	6,672,894
Fair Value	6,600,246
USDA Securities:
Held-to-maturity:
Unpaid Principal Balance	2,411,399	2,411,649
Amortized Cost	2,436,103	2,436,331
Allowance for losses	0	0
Unrealized Gains	221	95,741
Unrealized Losses	(44,593)	0
Fair Value	2,391,731	2,532,072
Trading:
Unpaid Principal Balance	3,370	4,299
Amortized Cost	3,481	4,433
Allowance for losses	0	0
Unrealized Gains	0	1
Unrealized Losses	(95)	(33)
Fair Value	3,386	$ 4,401
Trading securities, weighted-average yield		5.05%
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	4,317,820	$ 4,444,994
Amortized Cost	4,342,481	4,469,702
Allowance for losses	(160)	(132)
Unrealized Gains	3,365	107,000
Unrealized Losses	(78,134)	(12,764)
Fair Value	4,267,552	4,563,806
Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	6,659,760	6,122,240
Amortized cost	6,672,894	6,135,807
Allowance for losses	(681)	(263)
Unrealized Gains	45,780	213,025
Unrealized Losses	(117,747)	(20,010)
Fair Value	6,600,246	6,328,559
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(43)	26
Available-for-sale:
Unamortized Premium/(Discount)	(43)	26
Trading:
Unamortized Premium/(Discount)	(43)	26
Held-to-Maturity Securities \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	24,704	24,682
Available-for-sale:
Unamortized Premium/(Discount)	24,704	24,682
Trading:
Unamortized Premium/(Discount)	24,704	24,682
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,661	24,708
Available-for-sale:
Unamortized Premium/(Discount)	24,661	24,708
Trading:
Unamortized Premium/(Discount)	24,661	24,708
Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	13,134	13,567
Available-for-sale:
Unamortized Premium/(Discount)	13,134	13,567
Trading:
Unamortized Premium/(Discount)	13,134	13,567
Debt Securities, Trading \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	111	134
Available-for-sale:
Unamortized Premium/(Discount)	111	134
Trading:
Unamortized Premium/(Discount)	111	134
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Fair Value	11,000	12,400
Trading:
Derivative, notional amount	262,600	275,400
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	0	0
Amortized cost	11,918	12,297
Allowance for losses	0	0
Unrealized Gains	0	117
Unrealized Losses	(896)	0
Fair Value	11,022	12,414
Farmer Mac Guaranteed Securities \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	11,918	12,297
Available-for-sale:
Unamortized Premium/(Discount)	11,918	12,297
Trading:
Unamortized Premium/(Discount)	11,918	12,297
AgVantage
Trading:
Available-for-sale, accrued interest excluded	35,800	29,800
Held-to-maturity, accrued interest excluded	34,500	42,100
Trading securities, accrued interest excluded	100	100
AgVantage \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	1,880,383	2,003,486
Amortized Cost	1,880,383	2,003,486
Allowance for losses	(160)	(132)
Unrealized Gains	2,895	10,097
Unrealized Losses	(33,178)	(12,764)
Fair Value	1,849,940	2,000,687
AgVantage \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	6,659,760	6,122,240
Amortized cost	6,660,976	6,123,510
Allowance for losses	(681)	(263)
Unrealized Gains	45,780	212,908
Unrealized Losses	(116,851)	(20,010)
Fair Value	6,589,224	6,316,145
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)	1,216	1,270
Available-for-sale:
Unamortized Premium/(Discount)	1,216	1,270
Trading:
Unamortized Premium/(Discount)	1,216	1,270
Farmer Mac Guaranteed USDA Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	26,038	29,859
Amortized Cost	25,995	29,885
Allowance for losses	0	0
Unrealized Gains	249	1,162
Unrealized Losses	(363)	0
Fair Value	$ 25,881	31,047
Farmer Mac Guaranteed USDA Securities \| USDA Securities:
Trading:
Trading securities, weighted-average yield	5.06%
Farmer Mac Guaranteed USDA Securities \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	$ (43)	26
Available-for-sale:
Unamortized Premium/(Discount)	(43)	26
Trading:
Unamortized Premium/(Discount)	$ (43)	$ 26

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