Summary of Significant Accounting Policies - Consolidation of Variable Interest Entities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Loans held for investment, at amortized cost	$ 9,011,820	$ 8,314,096
Debt securities of consolidated trusts held by third parties	25,000,199	22,758,533
Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	7,607,226	6,328,559
Investment securities:
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	4,579,564	3,836,391
Agricultural Finance
Variable Interest Entity [Line Items]
Borrower remittances	8,100	32,800
Unamortized discount	(37,700)
Consolidated VIE \| On-balance sheet [Member]
Variable Interest Entity [Line Items]
Loans held for investment, at amortized cost	1,211,576	948,623
Debt securities of consolidated trusts held by third parties	1,181,948	981,379
Consolidated VIE \| Operating Segments \| On-balance sheet [Member] \| Agricultural Finance
Variable Interest Entity [Line Items]
Loans held for investment, at amortized cost	1,211,576	948,623
Debt securities of consolidated trusts held by third parties	1,181,948	981,379
Consolidated VIE \| Corporate, Non-Segment \| On-balance sheet [Member]
Variable Interest Entity [Line Items]
Loans held for investment, at amortized cost	0	0
Debt securities of consolidated trusts held by third parties	0	0
Unconsolidated VIE \| On-balance sheet [Member] \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	28,466	42,298
Maximum exposure to loss	31,208	42,155
Unconsolidated VIE \| On-balance sheet [Member] \| Investment securities:
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	3,138,619	2,258,219
Maximum exposure to loss	3,341,427	2,246,272
Unconsolidated VIE \| Off-balance sheet
Variable Interest Entity [Line Items]
Maximum exposure to loss	500,953	578,358
Unconsolidated VIE \| Operating Segments \| On-balance sheet [Member] \| Agricultural Finance \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	28,466	42,298
Maximum exposure to loss	31,208	42,155
Unconsolidated VIE \| Operating Segments \| On-balance sheet [Member] \| Agricultural Finance \| Investment securities:
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	0	0
Maximum exposure to loss	0	0
Unconsolidated VIE \| Operating Segments \| Off-balance sheet \| Agricultural Finance
Variable Interest Entity [Line Items]
Maximum exposure to loss	500,953	578,358
Unconsolidated VIE \| Corporate, Non-Segment \| On-balance sheet [Member] \| Farmer Mac Guaranteed Securities
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	0	0
Maximum exposure to loss	0	0
Unconsolidated VIE \| Corporate, Non-Segment \| On-balance sheet [Member] \| Investment securities:
Variable Interest Entity [Line Items]
Available-for-sale, at fair value	3,138,619	2,258,219
Maximum exposure to loss	3,341,427	2,246,272
Unconsolidated VIE \| Corporate, Non-Segment \| Off-balance sheet
Variable Interest Entity [Line Items]
Maximum exposure to loss	$ 0	$ 0

Amount, after accumulated amortization, of debt discount.

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