Financial Derivatives - Hedged Items in Fair Value Hedging Relationships (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Loans
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	$ 1,547,825	$ 1,692,609
Hedged Asset	(33,416)	111,333
Loans \| No hedge designation
HedgedItemsinFairValueHedgingRelationship [Line Items]
Hedged Asset	1,300
Long-term Debt
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	(3,986,760)	(3,006,140)
Hedged Liability	(23,739)	(53,240)
Farmer Mac Guaranteed Securities
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	4,113,973	4,244,027
Hedged Asset	214,023	$ 382,825
Farmer Mac Guaranteed Securities \| No hedge designation
HedgedItemsinFairValueHedgingRelationship [Line Items]
Hedged Asset	$ 1,500

[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=121590274&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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