Guarantees and Commitments - Off-Balance Sheet Guaranteed Securities (Details) - Unconsolidated VIE - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Guarantor Obligations [Line Items]
Total off-balance sheet Farmer Mac Guaranteed Securities	$ 547,239	$ 581,113
Agricultural Finance
Guarantor Obligations [Line Items]
Total off-balance sheet Farmer Mac Guaranteed Securities	544,484	578,358
Rural Infrastructure Finance
Guarantor Obligations [Line Items]
Total off-balance sheet Farmer Mac Guaranteed Securities	$ 2,755	$ 2,755