Fair Value Disclosures - Summary of Carrying Value and Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financial assets:
Financial derivatives	$ 28,855	$ 37,409
Guarantee and commitment fees receivable	49,809	47,151
Financial liabilities:
Financial derivatives	188,362	175,326
Guarantee and commitment obligation	47,607	46,582
Fair Value
Financial assets:
Cash and cash equivalents	782,318	861,002
Loans	9,718,846	9,666,710
Financial derivatives	28,855	37,409
Guarantee and commitment fees receivable	58,819	50,653
Financial liabilities:
Notes payable	24,224,819	23,591,330
Debt securities of consolidated trusts held by third parties	1,209,757	1,106,837
Financial derivatives	188,362	175,326
Guarantee and commitment obligation	56,617	50,083
Fair Value | Investment securities:
Financial assets:
Marketable securities	4,925,183	4,630,701
Fair Value | Farmer Mac Guaranteed Securities
Financial assets:
Marketable securities	9,170,053	8,573,781
Fair Value | USDA Securities
Financial assets:
Marketable securities	1,933,529	2,099,445
Carrying Amount
Financial assets:
Cash and cash equivalents	782,318	861,002
Loans	10,537,173	10,205,466
Financial derivatives	28,855	37,409
Guarantee and commitment fees receivable	49,809	47,151
Financial liabilities:
Notes payable	25,123,545	24,469,113
Debt securities of consolidated trusts held by third parties	1,334,014	1,181,948
Financial derivatives	188,362	175,326
Guarantee and commitment obligation	47,607	46,582
Carrying Amount | Investment securities:
Financial assets:
Marketable securities	4,924,253	4,628,268
Carrying Amount | Farmer Mac Guaranteed Securities
Financial assets:
Marketable securities	9,216,111	8,628,380
Carrying Amount | USDA Securities
Financial assets:
Marketable securities	$ 2,323,657	$ 2,411,601