Farmer Mac Guaranteed Securities and USDA Securities - Schedule of On-Balance Sheet Securities (Details) - USD ($) $ in Thousands		6 Months Ended
Dec. 31, 2022	Jun. 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 $15,737 and $12,514, respectively, related to consolidated trusts)	Accrued interest receivable (includes $15,737 and $12,514, respectively, related to consolidated trusts)
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	$ 1,021,275	$ 849,939
Amortized Cost	1,021,213	849,892
Allowance for losses	(59)	(64)
Unrealized Gains	355	273
Unrealized Losses	(54,954)	(47,286)
Fair Value	966,555	802,815
Available-for-sale:
Amortized cost		8,159,474
Fair Value		7,745,415
USDA Securities
Held-to-maturity:
Unpaid Principal Balance	2,384,946	2,312,632
Amortized Cost	2,409,834	2,336,212
Allowance for losses	0	0
Unrealized Gains	668	439
Unrealized Losses	(312,824)	(274,339)
Fair Value	2,097,678	2,062,312
Trading:
Unpaid Principal Balance	1,770	1,350
Amortized Cost	1,850	1,414
Allowance for losses	0	0
Unrealized Gains	0	0
Unrealized Losses	(83)	(66)
Fair Value	$ 1,767	1,348
Trading securities, weighted-average yield	4.84%
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	$ 3,406,221	3,162,571
Amortized Cost	3,431,047	3,186,104
Allowance for losses	(59)	(64)
Unrealized Gains	1,023	712
Unrealized Losses	(367,778)	(321,625)
Fair Value	3,064,233	2,865,127
Farmer Mac Guaranteed Securities:
Held-to-maturity:
Amortized Cost	1,021,154	849,828
Available-for-sale:
Unpaid Principal Balance	8,008,067	8,149,002
Amortized cost	8,019,495	8,159,474
Allowance for losses	(546)	(507)
Unrealized Gains	2,061	1,778
Unrealized Losses	(413,784)	(415,330)
Fair Value	7,607,226	7,745,415
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(62)	(47)
Available-for-sale:
Unamortized Premium/(Discount)	(62)	(47)
Trading:
Unamortized Premium/(Discount)	(62)	(47)
Held-to-Maturity Securities \| USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,888	23,580
Available-for-sale:
Unamortized Premium/(Discount)	24,888	23,580
Trading:
Unamortized Premium/(Discount)	24,888	23,580
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	24,826	23,533
Available-for-sale:
Unamortized Premium/(Discount)	24,826	23,533
Trading:
Unamortized Premium/(Discount)	24,826	23,533
Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	11,428	10,472
Available-for-sale:
Unamortized Premium/(Discount)	11,428	10,472
Trading:
Unamortized Premium/(Discount)	11,428	10,472
Debt Securities, Trading \| USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	80	64
Available-for-sale:
Unamortized Premium/(Discount)	80	64
Trading:
Unamortized Premium/(Discount)	80	64
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities
Available-for-sale:
Fair Value	7,800	7,600
Trading:
Derivative, notional amount	250,100	243,200
Farmer Mac Guaranteed Securities \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	0	0
Amortized cost	10,622	9,748
Allowance for losses	0	0
Unrealized Gains	0	0
Unrealized Losses	(2,775)	(2,143)
Fair Value	7,847	7,605
Farmer Mac Guaranteed Securities \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	10,622	9,748
Available-for-sale:
Unamortized Premium/(Discount)	10,622	9,748
Trading:
Unamortized Premium/(Discount)	10,622	9,748
AgVantage
Trading:
Available-for-sale, accrued interest excluded	51,500	56,800
Held-to-maturity, accrued interest excluded	44,400	33,600
Trading securities, accrued interest excluded	47	33
AgVantage \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	1,000,689	820,635
Amortized Cost	1,000,594	820,555
Allowance for losses	(59)	(64)
Unrealized Gains	353	260
Unrealized Losses	(54,098)	(46,500)
Fair Value	946,790	774,251
AgVantage \| Farmer Mac Guaranteed Securities:
Available-for-sale:
Unpaid Principal Balance	8,008,067	8,149,002
Amortized cost	8,008,873	8,149,726
Allowance for losses	(546)	(507)
Unrealized Gains	2,061	1,778
Unrealized Losses	(411,009)	(413,187)
Fair Value	7,599,379	7,737,810
AgVantage \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(95)	(80)
Available-for-sale:
Unamortized Premium/(Discount)	(95)	(80)
Trading:
Unamortized Premium/(Discount)	(95)	(80)
AgVantage \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	806	724
Available-for-sale:
Unamortized Premium/(Discount)	806	724
Trading:
Unamortized Premium/(Discount)	806	724
Farmer Mac Guaranteed USDA Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	20,586	29,304
Amortized Cost	20,619	29,337
Allowance for losses	0	0
Unrealized Gains	2	13
Unrealized Losses	(856)	(786)
Fair Value	19,765	$ 28,564
Farmer Mac Guaranteed USDA Securities \| USDA Securities
Trading:
Trading securities, weighted-average yield		5.51%
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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