SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Consolidation of Variable Interest Entities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost	$ 9,623,119	$ 9,008,979
Debt securities of consolidated trusts held by third parties	26,586,959	25,000,199
Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value	5,532,479	7,607,226
Investment securities
Variable Interest Entity [Line Items]
Carrying value	4,918,931	4,579,564
Agricultural Finance
Variable Interest Entity [Line Items]
Borrower remittances	6,000	8,100
Unamortized discount	87,100	37,700
Consolidated VIE \| On-balance sheet
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost	1,432,261	1,211,576
Debt securities of consolidated trusts held by third parties	1,351,069	1,181,948
Consolidated VIE \| On-balance sheet \| Agricultural Finance
Variable Interest Entity [Line Items]
Loans held for investment in consolidated trusts, at amortized cost		1,211,576
Debt securities of consolidated trusts held by third parties		1,181,948
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	1,432,261
Debt securities of consolidated trusts held by third parties	1,351,069
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	46,343	28,466
Maximum exposure to loss	45,952	31,208
Unconsolidated VIE \| On-balance sheet \| Investment securities
Variable Interest Entity [Line Items]
Carrying value	3,676,555	3,138,619
Maximum exposure to loss	3,862,006	3,341,427
Unconsolidated VIE \| On-balance sheet \| Agricultural Finance \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Carrying value		28,466
Maximum exposure to loss		31,208
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		3,138,619
Maximum exposure to loss		3,341,427
Unconsolidated VIE \| Off-balance sheet
Variable Interest Entity [Line Items]
Maximum exposure to loss	452,602	500,953
Unconsolidated VIE \| Off-balance sheet \| Agricultural Finance
Variable Interest Entity [Line Items]
Maximum exposure to loss		500,953
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	46,343
Maximum exposure to loss	45,952
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	452,602
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	3,676,555
Maximum exposure to loss	3,862,006
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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