Farmer Mac Guaranteed Securities and USDA Securities - Schedule of On-Balance Sheet Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	$ 2,033,345	$ 1,175,886
Amortized Cost	2,033,371	1,175,912
Allowance for losses	(132)	(120)
Unrealized Gains	11,259	25,259
Unrealized Losses	(12,764)	(61)
Fair Value	2,031,734	1,200,990
Available-for-sale:
Amortized cost	6,135,807
Fair Value	6,328,559
USDA Securities:
Held-to-maturity:
Unpaid Principal Balance	2,411,649	2,446,550
Amortized Cost	2,436,331	2,473,626
Allowance for losses	0	0
Unrealized Gains	95,741	157,748
Unrealized Losses	0	(560)
Fair Value	2,532,072	2,630,814
Trading:
Unpaid Principal Balance	4,299	6,413
Amortized Cost	4,433	6,611
Allowance for losses	0	0
Unrealized Gains	1	84
Unrealized Losses	(33)	0
Fair Value	4,401	$ 6,695
Trading securities, weighted-average yield		5.05%
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	4,444,994	$ 3,622,436
Amortized Cost	4,469,702	3,649,538
Allowance for losses	(132)	(120)
Unrealized Gains	107,000	183,007
Unrealized Losses	(12,764)	(621)
Fair Value	4,563,806	3,831,804
Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	6,122,240
Amortized cost	6,135,807	6,594,992
Allowance for losses	(263)
Unrealized Gains	213,025
Unrealized Losses	(20,010)
Fair Value	6,328,559	6,947,701
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	26	26
Available-for-sale:
Unamortized Premium/(Discount)	26	26
Trading:
Unamortized Premium/(Discount)	26	26
Held-to-Maturity Securities \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	24,682	27,076
Available-for-sale:
Unamortized Premium/(Discount)	24,682	27,076
Trading:
Unamortized Premium/(Discount)	24,682	27,076
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,708	27,102
Available-for-sale:
Unamortized Premium/(Discount)	24,708	27,102
Trading:
Unamortized Premium/(Discount)	24,708	27,102
Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	13,567
Available-for-sale:
Unamortized Premium/(Discount)	13,567
Trading:
Unamortized Premium/(Discount)	13,567
Debt Securities, Trading \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	134	198
Available-for-sale:
Unamortized Premium/(Discount)	134	198
Trading:
Unamortized Premium/(Discount)	134	198
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Fair Value	12,400
Trading:
Derivative, notional amount	275,400
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	0
Amortized cost	12,297
Allowance for losses	0
Unrealized Gains	117
Unrealized Losses	0
Fair Value	12,414
Farmer Mac Guaranteed Securities \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	12,297
Available-for-sale:
Unamortized Premium/(Discount)	12,297
Trading:
Unamortized Premium/(Discount)	12,297
AgVantage
Trading:
Available-for-sale, accrued interest excluded	29,800	32,300
Held-to-maturity, accrued interest excluded	42,100	44,700
Trading securities, accrued interest excluded	100	200
AgVantage \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	2,003,486	1,141,430
Amortized Cost	2,003,486	1,141,375
Allowance for losses	(132)	(120)
Unrealized Gains	10,097	23,986
Unrealized Losses	(12,764)	(61)
Fair Value	2,000,687	1,165,180
Available-for-sale:
Unpaid Principal Balance		6,593,518
Amortized cost		6,594,992
Allowance for losses		(310)
Unrealized Gains		368,257
Unrealized Losses		(15,238)
Fair Value		6,947,701
AgVantage \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	6,122,240
Amortized cost	6,123,510
Allowance for losses	(263)
Unrealized Gains	212,908
Unrealized Losses	(20,010)
Fair Value	6,316,145
AgVantage \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	0	(55)
Available-for-sale:
Unamortized Premium/(Discount)	0	(55)
Trading:
Unamortized Premium/(Discount)	0	(55)
AgVantage \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)		1,474
Available-for-sale:
Unamortized Premium/(Discount)		1,474
Trading:
Unamortized Premium/(Discount)		1,474
AgVantage \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	1,270
Available-for-sale:
Unamortized Premium/(Discount)	1,270
Trading:
Unamortized Premium/(Discount)	1,270
Farmer Mac Guaranteed USDA Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	29,859	34,456
Amortized Cost	29,885	34,537
Allowance for losses	0	0
Unrealized Gains	1,162	1,273
Unrealized Losses	0	0
Fair Value	$ 31,047	35,810
Farmer Mac Guaranteed USDA Securities \| USDA Securities:
Trading:
Trading securities, weighted-average yield	5.05%
Farmer Mac Guaranteed USDA Securities \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	$ 26	81
Available-for-sale:
Unamortized Premium/(Discount)	26	81
Trading:
Unamortized Premium/(Discount)	$ 26	$ 81

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