Fair Value Disclosures - Quantitative Information (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	$ 7,607,226
Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee Asset	4,467	$ 6,237
Recurring | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	7,607,226	6,328,559
Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	7,632,487	6,358,451	$ 6,973,567	$ 7,170,850
Guarantee Asset	4,467	6,237
Recurring | Level 3 | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	7,607,226	6,328,559
Floating rate auction-rate certificates backed by Government guaranteed student loans | Recurring | Level 3 | Floating Interest Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	19,027	19,254	19,171	18,912
Farmer Mac Guaranteed Securities | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	7,800	12,400
Farmer Mac Guaranteed Securities | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	7,607,226	6,328,559	6,947,701	7,143,025
USDA Securities: | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	1,767	4,401	6,695	8,913
AgVantage Securities | Recurring | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	7,599,379	6,316,145
AgVantage Securities | Recurring | Level 3 | Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale, at fair value	7,599,379	6,316,145
AgVantage Securities | Farmer Mac Guaranteed Securities | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	7,599,379	6,316,145	6,947,701	$ 7,143,025
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	7,847	12,414
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	7,847	12,414
Farmer Mac Guaranteed USDA Securities | Farmer Mac Guaranteed Securities | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 7,847	$ 12,414	$ 0
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	0.968	0.980
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	0.968	0.980
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	0.968	0.980
Discount rate | Minimum | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input	0.054	0.054
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	0.047	0.009
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	0.048	0.023
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	0.051	0.014
Discount rate | Maximum | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input	0.059	0.058
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	0.061	0.021
Discount rate | Maximum | 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	0.053	0.028
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	0.057	0.031
Discount rate | Weighted Average | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input	0.057	0.056
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	0.051	0.017
Discount rate | Weighted Average | 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	0.051	0.026
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	0.028
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	0.08	0.08
CPR | Minimum | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input	0.08	0.07
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	0.19	0.25
CPR | Maximum | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input		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	0.27	0.42
CPR | Weighted Average | Discounted cash flow | Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Guarantee asset, measurement input		0.08
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	0.25	0.39