Related Party Transactions - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Commitment fees receivable	$ 100	$ 100
Guarantees of losses, percentage	10.00%
Zions Bancorporation, National Association
Related Party Transaction [Line Items]
Related party percent of Farmer Mac's outstanding business volume	3.50%	3.40%
Servicing fees	$ 10,400	$ 11,000	$ 11,800
CFC
Related Party Transaction [Line Items]
Transaction with related party, percent of volume	12.00%	18.40%	9.10%
Related party percent of Farmer Mac's outstanding business volume	18.70%	19.50%
Servicing fees	$ 3,400	$ 3,300	$ 3,300
Interest receivables	18,200	7,800
Interest income	79,400	50,000	63,100
Commitment fees earned	1,100	1,200	1,300
CoBank
Related Party Transaction [Line Items]
Servicing fees	3,500	3,200	2,300
AgFirst Farm Credit Bank
Related Party Transaction [Line Items]
Commitment fees receivable	100	100
Commitment fees earned	1,200	1,200	1,200
Guarantee fees	15	19	25
AgFirst Farm Credit Bank \| Guarantee Obligations
Related Party Transaction [Line Items]
Unpaid principal balance	0	11,000	32,500
Outstanding balance	387,100	363,900
AgFirst Farm Credit Bank \| Performance Guarantee
Related Party Transaction [Line Items]
Outstanding balance	2,200	4,000
Farm Credit Bank of Texas
Related Party Transaction [Line Items]
Servicing fees	100	100	100
Commitment fees earned	2,900	1,900	$ 1,200
Farm Credit Bank of Texas \| Guarantee Obligations
Related Party Transaction [Line Items]
Outstanding balance	$ 881,600	$ 625,600
Class A voting common stock \| Zions Bancorporation, National Association
Related Party Transaction [Line Items]
Ownership by a related party	31.20%
Class A voting common stock \| CFC
Related Party Transaction [Line Items]
Ownership by a related party	7.91%
Common Class B \| CoBank
Related Party Transaction [Line Items]
Ownership by a related party	32.60%
Common Class B \| AgFirst Farm Credit Bank
Related Party Transaction [Line Items]
Ownership by a related party	16.80%
Common Class B \| Farm Credit Bank of Texas
Related Party Transaction [Line Items]
Ownership by a related party	7.70%
Agricultural Finance \| Zions Bancorporation, National Association
Related Party Transaction [Line Items]
Transaction with related party, percent of volume of loan purchases	12.90%	8.00%	7.10%
Transaction with related party, percent of volume	9.60%	5.60%	6.20%
USDA Guarantee \| Zions Bancorporation, National Association
Related Party Transaction [Line Items]
Transaction with related party, percent of volume	1.50%	2.10%	1.40%
Rural Utilities \| CFC
Related Party Transaction [Line Items]
Transaction with related party, percent of volume of loan purchases	46.70%	36.90%	36.70%
Rural Utilities \| CoBank
Related Party Transaction [Line Items]
Transaction with related party, percent of volume of loan purchases	45.40%	60.20%	56.00%
AgVantage Securities \| CFC
Related Party Transaction [Line Items]
Transaction with related party, percent of volume	13.40%	37.00%	19.20%
AgVantage Securities \| CFC \| Guarantee Obligations
Related Party Transaction [Line Items]
Unpaid principal balance	$ 670,000	$ 1,450,000	$ 250,000
Mortgages \| Agricultural Finance \| Bath State Bank
Related Party Transaction [Line Items]
Unpaid principal balance	2,100	5,000
Mortgages \| Agricultural Finance \| Farm Credit of Florida [Member]
Related Party Transaction [Line Items]
Unpaid principal balance	0	1,100	200
Mortgages \| Rural Utilities
Related Party Transaction [Line Items]
Unpaid principal balance	$ 376,000	$ 207,500	416,800
Unfunded Loan Commitment \| CoBank
Related Party Transaction [Line Items]
Transaction with related party, percent of volume of loan purchases	6.30%	5.60%
USDA Securities: \| USDA Guarantee \| Zions Bancorporation, National Association
Related Party Transaction [Line Items]
Unpaid principal balance	$ 4,171	$ 9,565	10,764
USDA Securities: \| USDA Guarantee \| Bath State Bank
Related Party Transaction [Line Items]
Unpaid principal balance	$ 0	$ 2,300	$ 9,200

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Guarantees Of Losses, Percentage

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Related Party Transaction, Related Party's percent of total Program

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Related Party's percent of Farmer Mac Total Outstanding Book of Business

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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