FAIR VALUE DISCLOSURES - Quantitative Information (Details) $ in Thousands	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair  Value	$ 13,580,285	$ 11,467,560
Other Assets	4,897	5,382
Auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair  Value		19,476
AgVantage
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair  Value	6,730,917	5,505,531
Interest-Only Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair  Value	8,203	9,015
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other Assets	4,897	5,382
Level 3 | Auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair  Value		19,476
Level 3 | AgVantage
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair  Value	6,730,917	5,505,531
Level 3 | Interest-Only Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair  Value	$ 8,203	$ 9,015
Range of broker quotes | Minimum | Indicative bids | Level 3 | Auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input		0.990
Range of broker quotes | Maximum | Indicative bids | Level 3 | Auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input		0.990
Range of broker quotes | Weighted Average | Indicative bids | Level 3 | Auction-rate certificates backed by Government guaranteed student loans
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input		0.990
Discount rate | Discounted cash flow | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other asset, measurement input	0.078
Discount rate | Discounted cash flow | Level 3 | Interest-Only Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.078
Discount rate | Minimum | Discounted cash flow | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other asset, measurement input		0.079
Discount rate | Minimum | Discounted cash flow | Level 3 | AgVantage
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.043	0.050
Discount rate | Minimum | Discounted cash flow | Level 3 | Interest-Only Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input		0.079
Discount rate | Maximum | Discounted cash flow | Level 3 | AgVantage
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.049	0.055
Discount rate | Weighted Average | Discounted cash flow | Level 3 | AgVantage
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.045	0.051
CPR | Discounted cash flow | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other asset, measurement input	0.03	0.03
CPR | Discounted cash flow | Level 3 | Interest-Only Farmer Mac Guaranteed Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Investment securities, measurement input	0.03	0.03