LOANS - Schedule of Composition of Loan Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 11,360,197	$ 10,549,845
Allowance for losses	(16,031)	(15,089)
Total loans, net of allowance	11,039,349	10,205,466
Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	11,360,197	10,549,845
Unamortized premiums, discounts, fair value hedge basis adjustment, and other cost basis adjustments	(304,817)	(329,290)
Total loans	11,055,380	10,220,555
Allowance for losses	(16,031)	(15,089)
Total loans, net of allowance	11,039,349	10,205,466
Agricultural Finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	7,825,434	7,528,579
Agricultural Finance | Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	7,825,434	7,528,579
Allowance for losses	(6,884)	(6,775)	$ (3,442)	$ (3,745)
Farm & Ranch
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	6,565,711	6,362,326
Farm & Ranch | Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	6,565,711	6,362,326
Allowance for losses	(3,936)	(4,044)	(2,882)	(3,404)
Corporate AgFinance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,259,723	1,166,253
Corporate AgFinance | Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,259,723	1,166,253
Allowance for losses	(2,948)	(2,731)	(560)	(341)
Rural Infrastructure Finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	3,534,763	3,021,266
Rural Infrastructure Finance | Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	3,534,763	3,021,266
Allowance for losses	(9,147)	(8,314)	$ (10,599)	$ (10,087)
Unsecuritized
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	9,927,936	9,338,269
Unamortized premiums, discounts, fair value hedge basis adjustment, and other cost basis adjustments	(304,817)	(329,290)
Total loans	9,623,119	9,008,979
Allowance for losses	(15,588)	(14,629)
Total loans, net of allowance	9,607,531	8,994,350
Unsecuritized | Agricultural Finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	6,393,173	6,317,003
Unsecuritized | Farm & Ranch
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	5,133,450	5,150,750
Unsecuritized | Corporate AgFinance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,259,723	1,166,253
Unsecuritized | Rural Infrastructure Finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	3,534,763	3,021,266
In Consolidated Trusts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,432,261	1,211,576
Unamortized premiums, discounts, fair value hedge basis adjustment, and other cost basis adjustments	0	0
Total loans	1,432,261	1,211,576
Allowance for losses	(443)	(460)
Total loans, net of allowance	1,431,818	1,211,116
In Consolidated Trusts | Agricultural Finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,432,261	1,211,576
In Consolidated Trusts | Farm & Ranch
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,432,261	1,211,576
In Consolidated Trusts | Corporate AgFinance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	0	0
In Consolidated Trusts | Rural Infrastructure Finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 0	$ 0