SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Consolidation of Variable Interest Entities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Variable Interest Entity [Line Items]
Carrying value	$ 13,580,285	$ 11,467,560
Farmer Mac Guaranteed USDA Securities
Variable Interest Entity [Line Items]
Guarantee and commitment obligation	$ 5,000	$ 5,600
Weighted-average remaining maturity	20 years 8 months 12 days	21 years 2 months 12 days
Unconsolidated VIE \| On-balance sheet \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value	$ 80,570	$ 59,317
Maximum exposure to loss	80,384	58,985
Unconsolidated VIE \| Off-balance sheet
Variable Interest Entity [Line Items]
Maximum exposure to loss	$ 386,057	$ 426,310

Weighted Average Remaining Maturity, Loans Underlying Guarantees Not Held By Transferor

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- Definition

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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