Fair Value Disclosures - Summary of Carrying Value and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Financial assets:
Financial derivatives	$ 30,011	$ 19,139
Guarantee and commitment fees receivable	44,388	45,538
Financial liabilities:
Guarantee and commitment obligation	42,990	43,926
Fair Value
Financial assets:
Cash and cash equivalents	909,430	908,785
Loans	9,473,493	9,814,642
Financial derivatives	30,011	19,139
Guarantee and commitment fees receivable	46,641	42,533
Financial liabilities:
Notes payable	22,811,953	22,716,791
Debt securities of consolidated trusts held by third parties	818,159	1,005,306
Financial derivatives	127,983	34,248
Guarantee and commitment obligation	45,243	40,920
Fair Value | Investment securities:
Financial assets:
Marketable securities	4,292,220	3,884,202
Fair Value | Farmer Mac Guaranteed Securities
Financial assets:
Marketable securities	8,096,651	8,360,293
Fair Value | USDA Securities:
Financial assets:
Marketable securities	2,252,884	2,536,473
Carrying Amount
Financial assets:
Cash and cash equivalents	909,430	908,785
Loans	9,734,013	9,248,678
Financial derivatives	30,011	19,139
Guarantee and commitment fees receivable	44,388	45,538
Financial liabilities:
Notes payable	23,474,095	22,716,156
Debt securities of consolidated trusts held by third parties	866,107	981,379
Financial derivatives	127,983	34,248
Guarantee and commitment obligation	42,990	43,926
Carrying Amount | Investment securities:
Financial assets:
Marketable securities	4,292,581	3,882,590
Carrying Amount | Farmer Mac Guaranteed Securities
Financial assets:
Marketable securities	8,139,681	8,361,798
Carrying Amount | USDA Securities:
Financial assets:
Marketable securities	$ 2,433,105	$ 2,440,732