Financial Derivatives - Hedged Items in Fair Value Hedging Relationships (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Available-for-Sale Securities
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	$ 1,138,569	$ 876,063
Hedged Asset	(153,592)	(107,107)
Loans
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	1,570,732	1,623,301
Hedged Asset	(425,105)	(327,278)
Long-term Debt
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	(12,614,569)	(12,151,382)
Hedged Liability	478,942	531,086
Farmer Mac Guaranteed Securities:
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	5,025,413	4,814,784
Hedged Asset	$ (463,464)	$ (346,873)

[Line Items] for HedgedItemsinFairValueHedgingRelationship [Table]

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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

No definition available.

+ Details

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4EE

+ Details

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4EE

+ Details

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