SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Consolidation of Variable Interest Entities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost	$ 11,183,408	$ 9,623,119
Debt securities of consolidated trusts held by third parties	27,520,173	26,586,959
Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value	5,514,546	5,532,479
Investment securities
Variable Interest Entity [Line Items]
Carrying value	5,953,014	4,918,931
Agricultural Finance
Variable Interest Entity [Line Items]
Borrower remittances	4,700	6,000
Unamortized discount	113,200	87,100
Consolidated VIE \| On-balance sheet
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost	2,038,283	1,432,261
Debt securities of consolidated trusts held by third parties	1,929,628	1,351,069
Consolidated VIE \| On-balance sheet \| Agricultural Finance
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost		1,432,261
Debt securities of consolidated trusts held by third parties		1,351,069
Consolidated VIE \| On-balance sheet \| Treasury
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost		0
Debt securities of consolidated trusts held by third parties		0
Consolidated VIE \| Operating Segments \| On-balance sheet \| Agricultural Finance
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost	2,038,283
Debt securities of consolidated trusts held by third parties	1,929,628
Consolidated VIE \| Corporate, non-segment \| On-balance sheet
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost	0
Debt securities of consolidated trusts held by third parties	0
Unconsolidated VIE \| On-balance sheet \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value	59,317	46,343
Maximum exposure to loss	58,985	45,952
Unconsolidated VIE \| On-balance sheet \| Investment securities
Variable Interest Entity [Line Items]
Carrying value	4,212,258	3,676,555
Maximum exposure to loss	4,547,397	3,862,006
Unconsolidated VIE \| On-balance sheet \| Agricultural Finance \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value		46,343
Maximum exposure to loss		45,952
Unconsolidated VIE \| On-balance sheet \| Agricultural Finance \| Investment securities
Variable Interest Entity [Line Items]
Carrying value		0
Maximum exposure to loss		0
Unconsolidated VIE \| On-balance sheet \| Treasury \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value		0
Maximum exposure to loss		0
Unconsolidated VIE \| On-balance sheet \| Treasury \| Investment securities
Variable Interest Entity [Line Items]
Carrying value		3,676,555
Maximum exposure to loss		3,862,006
Unconsolidated VIE \| Off-balance sheet
Variable Interest Entity [Line Items]
Maximum exposure to loss	426,310	452,602
Unconsolidated VIE \| Off-balance sheet \| Agricultural Finance
Variable Interest Entity [Line Items]
Maximum exposure to loss		452,602
Unconsolidated VIE \| Off-balance sheet \| Treasury
Variable Interest Entity [Line Items]
Maximum exposure to loss		$ 0
Unconsolidated VIE \| Operating Segments \| On-balance sheet \| Agricultural Finance \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value	59,317
Maximum exposure to loss	58,985
Unconsolidated VIE \| Operating Segments \| On-balance sheet \| Agricultural Finance \| Investment securities
Variable Interest Entity [Line Items]
Carrying value	0
Maximum exposure to loss	0
Unconsolidated VIE \| Operating Segments \| Off-balance sheet \| Agricultural Finance
Variable Interest Entity [Line Items]
Maximum exposure to loss	426,310
Unconsolidated VIE \| Corporate, non-segment \| On-balance sheet \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value	0
Maximum exposure to loss	0
Unconsolidated VIE \| Corporate, non-segment \| On-balance sheet \| Investment securities
Variable Interest Entity [Line Items]
Carrying value	4,212,258
Maximum exposure to loss	4,547,397
Unconsolidated VIE \| Corporate, non-segment \| Off-balance sheet
Variable Interest Entity [Line Items]
Maximum exposure to loss	$ 0

Amount, after accumulated amortization, of debt discount.

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