Farmer Mac Guaranteed Securities and USDA Securities - Schedule of On-Balance Sheet Securities (Details) - USD ($) $ in Thousands		9 Months Ended
Dec. 31, 2022	Sep. 30, 2023
Trading:
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Accrued interest receivable (includes $10,666 and $12,514, respectively, related to consolidated trusts)	Accrued interest receivable (includes $10,666 and $12,514, respectively, related to consolidated trusts)
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	$ 1,021,275	$ 4,187,966
Amortized Cost	1,021,213	4,157,610
Allowance for losses	(59)	(196)
Unrealized Gains	355	4,525
Unrealized Losses	(54,954)	(50,583)
Fair Value	966,555	4,111,356
Available-for-sale:
Amortized cost		5,536,437
Fair Value		5,058,697
USDA Securities
Held-to-maturity:
Unpaid Principal Balance	2,384,946	2,299,407
Amortized Cost	2,409,834	2,322,355
Allowance for losses	0	0
Unrealized Gains	668	194
Unrealized Losses	(312,824)	(390,322)
Fair Value	2,097,678	1,932,227
Trading:
Unpaid Principal Balance	1,770	1,314
Amortized Cost	1,850	1,371
Allowance for losses	0	0
Unrealized Gains	0	0
Unrealized Losses	(83)	(69)
Fair Value	$ 1,767	1,302
Trading securities, weighted-average yield	4.84%
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	$ 3,406,221	6,487,373
Amortized Cost	3,431,047	6,479,965
Allowance for losses	(59)	(196)
Unrealized Gains	1,023	4,719
Unrealized Losses	(367,778)	(440,905)
Fair Value	3,064,233	6,043,583
Farmer Mac Guaranteed Securities:
Held-to-maturity:
Amortized Cost	1,021,154	4,157,414
Available-for-sale:
Unpaid Principal Balance	8,008,067	5,526,857
Amortized cost	8,019,495	5,536,437
Allowance for losses	(546)	(374)
Unrealized Gains	2,061	409
Unrealized Losses	(413,784)	(477,775)
Fair Value	7,607,226	5,058,697
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(62)	(30,356)
Available-for-sale:
Unamortized Premium/(Discount)	(62)	(30,356)
Trading:
Unamortized Premium/(Discount)	(62)	(30,356)
Held-to-Maturity Securities \| USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,888	22,948
Available-for-sale:
Unamortized Premium/(Discount)	24,888	22,948
Trading:
Unamortized Premium/(Discount)	24,888	22,948
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,826	(7,408)
Available-for-sale:
Unamortized Premium/(Discount)	24,826	(7,408)
Trading:
Unamortized Premium/(Discount)	24,826	(7,408)
Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	11,428	9,580
Available-for-sale:
Unamortized Premium/(Discount)	11,428	9,580
Trading:
Unamortized Premium/(Discount)	11,428	9,580
Debt Securities, Trading \| USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	80	57
Available-for-sale:
Unamortized Premium/(Discount)	80	57
Trading:
Unamortized Premium/(Discount)	80	57
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Fair Value	7,800	10,000
Trading:
Derivative, notional amount	250,100	239,100
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	0	0
Amortized cost	10,622	9,580
Allowance for losses	0	0
Unrealized Gains	0	409
Unrealized Losses	(2,775)	0
Fair Value	7,847	9,989
Farmer Mac Guaranteed Securities \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	10,622	9,580
Available-for-sale:
Unamortized Premium/(Discount)	10,622	9,580
Trading:
Unamortized Premium/(Discount)	10,622	9,580
AgVantage
Trading:
Available-for-sale, accrued interest excluded	51,500	53,300
Held-to-maturity, accrued interest excluded	44,400	58,900
Trading securities, accrued interest excluded	47	38
AgVantage \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	1,000,689	4,158,857
Amortized Cost	1,000,594	4,128,468
Allowance for losses	(59)	(196)
Unrealized Gains	353	4,525
Unrealized Losses	(54,098)	(49,221)
Fair Value	946,790	4,083,576
AgVantage \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	8,008,067	5,526,857
Amortized cost	8,008,873	5,526,857
Allowance for losses	(546)	(374)
Unrealized Gains	2,061	0
Unrealized Losses	(411,009)	(477,775)
Fair Value	7,599,379	5,048,708
AgVantage \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(95)	(30,389)
Available-for-sale:
Unamortized Premium/(Discount)	(95)	(30,389)
Trading:
Unamortized Premium/(Discount)	(95)	(30,389)
AgVantage \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	806	0
Available-for-sale:
Unamortized Premium/(Discount)	806	0
Trading:
Unamortized Premium/(Discount)	806	0
Farmer Mac Guaranteed USDA Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	20,586	29,109
Amortized Cost	20,619	29,142
Allowance for losses	0	0
Unrealized Gains	2	0
Unrealized Losses	(856)	(1,362)
Fair Value	19,765	$ 27,780
Farmer Mac Guaranteed USDA Securities \| USDA Securities
Trading:
Trading securities, weighted-average yield		5.50%
Farmer Mac Guaranteed USDA Securities \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	33	$ 33
Available-for-sale:
Unamortized Premium/(Discount)	33	33
Trading:
Unamortized Premium/(Discount)	$ 33	$ 33

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