FAIR VALUE DISCLOSURES - Schedule of Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net Income	Net Income
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]	Comprehensive Income (Loss), Net of Tax, Attributable to Parent	Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Level 3 \| Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 5,558,633	$ 7,632,487
Purchases	50,000	687,650
Settlements	(64,391)	(142,437)
Allowance for Losses	28	36
Realized and unrealized losses included in Income	(80,708)	93,701
Unrealized gains/(losses) included in Other Comprehensive Income	29,206	(20,977)
Ending Balance	5,492,768	8,250,460
Available-for-sale securities \| Level 3 \| Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	19,082	19,027
Purchases	0	0
Settlements	0	0
Allowance for Losses	1	4
Realized and unrealized losses included in Income	0	0
Unrealized gains/(losses) included in Other Comprehensive Income	198	0
Ending Balance	19,281	19,031
Floating rate auction-rate certificates backed by Government guaranteed student loans \| Floating interest rate \| Level 3 \| Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	19,082	19,027
Purchases	0	0
Settlements	0	0
Allowance for Losses	1	4
Realized and unrealized losses included in Income	0	0
Unrealized gains/(losses) included in Other Comprehensive Income	198	0
Ending Balance	19,281	19,031
Farmer Mac Guaranteed Securities \| Level 3 \| Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	5,532,479	7,607,226
Purchases	50,000	687,650
Settlements	(64,132)	(141,819)
Allowance for Losses	27	32
Realized and unrealized losses included in Income	(80,694)	93,342
Unrealized gains/(losses) included in Other Comprehensive Income	29,008	(20,977)
Ending Balance	5,466,688	8,225,454
Farmer Mac Guaranteed Securities \| Level 3 \| Recurring \| AgVantage Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	5,522,712	7,599,379
Purchases	50,000	687,650
Settlements	(63,955)	(141,386)
Allowance for Losses	27	32
Realized and unrealized losses included in Income	(80,694)	93,342
Unrealized gains/(losses) included in Other Comprehensive Income	29,107	(21,597)
Ending Balance	5,457,197	8,217,420
Farmer Mac Guaranteed Securities \| Level 3 \| Recurring \| Farmer Mac Guaranteed USDA Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	9,767	7,847
Purchases	0	0
Settlements	(177)	(433)
Allowance for Losses	0	0
Realized and unrealized losses included in Income	0	0
Unrealized gains/(losses) included in Other Comprehensive Income	(99)	620
Ending Balance	9,491	8,034
USDA Securities: \| Level 3 \| Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	1,241	1,767
Purchases	0	0
Settlements	(174)	(387)
Allowance for Losses	0	0
Realized and unrealized losses included in Income	(1)	25
Unrealized gains/(losses) included in Other Comprehensive Income	0	0
Ending Balance	1,066	1,405
Guarantee and commitment obligations: \| Level 3 \| Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	5,831	4,467
Purchases	0	0
Settlements	(85)	(231)
Allowance for Losses	0	0
Realized and unrealized losses included in Income	(13)	334
Unrealized gains/(losses) included in Other Comprehensive Income	0	0
Ending Balance	5,733	4,570
Guarantee and commitment obligations: \| Level 3 \| Recurring \| Guarantee Asset
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	5,831	4,467
Purchases	0	0
Settlements	(85)	(231)
Allowance for Losses	0	0
Realized and unrealized losses included in Income	(13)	334
Unrealized gains/(losses) included in Other Comprehensive Income	0	0
Ending Balance	$ 5,733	$ 4,570

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Allowance for Credit Loss

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Indicates line item in statement in which net income is reported that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

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