FAIR VALUE DISCLOSURES - Quantitative Information (Details) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	$ 5,761,691
Floating interest rate | Floating rate auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	19,478	$ 19,082
Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee Asset	5,556	5,831
Recurring | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	5,761,691	5,532,479
Recurring | Floating interest rate | Floating rate auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	19,478	19,082
Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee Asset	5,556	5,831
Recurring | Level 3 | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	5,761,691	5,532,479
Recurring | Level 3 | Floating interest rate | Floating rate auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	19,478	19,082
Farmer Mac Guaranteed Securities | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	9,300	9,800
USDA Securities | Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trading	842	1,241
USDA Securities | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trading	842	1,241
AgVantage Securities | Recurring | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	5,752,385	5,522,712
AgVantage Securities | Recurring | Level 3 | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	5,752,385	5,522,712
Farmer Mac Guaranteed USDA Securities | Recurring | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	9,306	9,767
Farmer Mac Guaranteed USDA Securities | Recurring | Level 3 | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	9,306	9,767
USDA Securities | USDA Securities | Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trading	842	1,241
USDA Securities | USDA Securities | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Trading	$ 842	$ 1,241
Range of broker quotes | Minimum | Floating rate auction-rate certificates backed by Government guaranteed student loans | Indicative bids | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.990	0.970
Range of broker quotes | Maximum | Floating rate auction-rate certificates backed by Government guaranteed student loans | Indicative bids | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.990	0.970
Range of broker quotes | Weighted Average | Floating rate auction-rate certificates backed by Government guaranteed student loans | Indicative bids | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.990	0.970
Discount rate | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input	0.083
Discount rate | Farmer Mac Guaranteed USDA Securities | Farmer Mac Guaranteed Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.083
Discount rate | Minimum | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input		0.083
Discount rate | Minimum | AgVantage Securities | Farmer Mac Guaranteed Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.043	0.047
Discount rate | Minimum | Farmer Mac Guaranteed USDA Securities | Farmer Mac Guaranteed Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input		0.083
Discount rate | Minimum | USDA Securities | USDA Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
USDA securities, measurement input	0.052	0.054
Discount rate | Maximum | AgVantage Securities | Farmer Mac Guaranteed Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.053	0.054
Discount rate | Maximum | USDA Securities | USDA Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
USDA securities, measurement input	0.053	0.054
Discount rate | Weighted Average | AgVantage Securities | Farmer Mac Guaranteed Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.045	0.050
Discount rate | Weighted Average | USDA Securities | USDA Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
USDA securities, measurement input	0.053	0.054
CPR | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input	0.03	0.03
CPR | Farmer Mac Guaranteed USDA Securities | Farmer Mac Guaranteed Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.03	0.03
CPR | Minimum | USDA Securities | USDA Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
USDA securities, measurement input	0.13	0.12
CPR | Maximum | USDA Securities | USDA Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
USDA securities, measurement input	0.13	0.12
CPR | Weighted Average | USDA Securities | USDA Securities | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
USDA securities, measurement input	0.13	0.12