Financial Derivatives - Hedged Items in Fair Value Hedging Relationships (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Available-for-Sale Securities
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	$ 520,485	$ 458,653
Hedged Asset	(33,944)	(1,218)
Loans
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	1,672,092	1,668,142
Hedged Asset	(115,775)	13,832
Loans \| No hedge designation
HedgedItemsinFairValueHedgingRelationship [Line Items]
Hedged Asset	1,200
Long-term Debt
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	(8,024,125)	(7,083,535)
Hedged Liability	279,191	42,377
Farmer Mac Guaranteed Securities
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	4,826,536	4,276,002
Hedged Asset	(4,129)	206,520
Farmer Mac Guaranteed Securities \| No hedge designation
HedgedItemsinFairValueHedgingRelationship [Line Items]
Hedged Asset	$ 1,200	$ 1,300

[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.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

+ 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

+ Details

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