GUARANTEES AND COMMITMENTS - Credit Quality Indicators (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Total
Total	$ 10,668,844		$ 10,668,844		$ 9,623,119
Agricultural Finance
Total
Current period charge-offs	0	$ 0	4,043	$ 0
Rural Infrastructure Finance
Year One
Total	935,251		935,251		618,946
Current period charge-offs	0	0	0	0
Year Two
Total	547,129		547,129		720,522
Current period charge-offs	0	0	0	0
Year Three
Total	641,415		641,415		187,746
Current period charge-offs	0	0	0	0
Year Four
Total	176,273		176,273		593,841
Current period charge-offs	0	0	0	0
Year Five
Total	565,944		565,944		701,937
Current period charge-offs	0	0	0	0
Prior
Total	1,242,792		1,242,792		611,548
Current period charge-offs	0	0	0	0
Revolving Loans - Amortized Cost Basis
Total	274,551		274,551		100,223
Current period charge-offs	0	0	0	0
Total
Total	4,383,355		4,383,355		3,534,763
Current period charge-offs	0	0	0	0
Acceptable | Rural Infrastructure Finance
Year One
Total	932,310		932,310		618,946
Year Two
Total	536,679		536,679		681,272
Year Three
Total	582,812		582,812		187,746
Year Four
Total	176,273		176,273		593,841
Year Five
Total	565,944		565,944		701,937
Prior
Total	1,242,792		1,242,792		611,548
Revolving Loans - Amortized Cost Basis
Total	274,551		274,551		100,223
Total
Total	4,311,361		4,311,361		3,495,513
Special mention | Rural Infrastructure Finance
Year One
Total	2,941		2,941		0
Year Two
Total	10,450		10,450		9,850
Year Three
Total	34,475		34,475		0
Year Four
Total	0		0		0
Year Five
Total	0		0		0
Prior
Total	0		0		0
Revolving Loans - Amortized Cost Basis
Total	0		0		0
Total
Total	47,866		47,866		9,850
Substandard | Rural Infrastructure Finance
Year One
Total	0		0		0
Year Two
Total	0		0		29,400
Year Three
Total	24,128		24,128		0
Year Four
Total	0		0		0
Year Five
Total	0		0		0
Prior
Total	0		0		0
Revolving Loans - Amortized Cost Basis
Total	0		0		0
Total
Total	24,128		24,128		29,400
Long-Term Standby Purchase Commitments and Guaranteed Securities
Total
Total	3,808,570		3,808,570		3,932,857
Long-Term Standby Purchase Commitments and Guaranteed Securities | Agricultural Finance
Year One
Total	12,104		12,104		169,429
Current period charge-offs	0	0	0	0
Year Two
Total	132,985		132,985		246,512
Current period charge-offs	0	0	0	0
Year Three
Total	234,087		234,087		517,862
Current period charge-offs	0	0	0	0
Year Four
Total	494,402		494,402		535,398
Current period charge-offs	0	0	0	0
Year Five
Total	529,317		529,317		266,882
Current period charge-offs	0	0	0	0
Prior
Total	1,369,941		1,369,941		1,256,770
Current period charge-offs	0	0	0	0
Revolving Loans - Amortized Cost Basis
Total	424,571		424,571		404,991
Current period charge-offs	0	0	0	0
Total
Total	3,197,407		3,197,407		3,397,844
Current period charge-offs	0	0	0	0
Long-Term Standby Purchase Commitments and Guaranteed Securities | Rural Infrastructure Finance
Year One
Total	0		0		0
Current period charge-offs	0	0	0	0
Year Two
Total	0		0		0
Current period charge-offs	0	0	0	0
Year Three
Total	0		0		0
Current period charge-offs	0	0	0	0
Year Four
Total	0		0		0
Current period charge-offs	0	0	0	0
Year Five
Total	0		0		0
Current period charge-offs	0	0	0	0
Prior
Total	363,689		363,689		419,190
Current period charge-offs	0	0	0	0
Revolving Loans - Amortized Cost Basis
Total	247,474		247,474		115,823
Current period charge-offs	0	0	0	0
Total
Total	611,163		611,163		535,013
Current period charge-offs	0	$ 0	0	$ 0
Long-Term Standby Purchase Commitments and Guaranteed Securities | Acceptable | Agricultural Finance
Year One
Total	12,104		12,104		169,429
Year Two
Total	127,022		127,022		246,441
Year Three
Total	219,900		219,900		515,396
Year Four
Total	478,659		478,659		534,395
Year Five
Total	516,045		516,045		264,815
Prior
Total	1,297,238		1,297,238		1,185,811
Revolving Loans - Amortized Cost Basis
Total	411,223		411,223		391,335
Total
Total	3,062,191		3,062,191		3,307,622
Long-Term Standby Purchase Commitments and Guaranteed Securities | Acceptable | Rural Infrastructure Finance
Year One
Total	0		0		0
Year Two
Total	0		0		0
Year Three
Total	0		0		0
Year Four
Total	0		0		0
Year Five
Total	0		0		0
Prior
Total	363,689		363,689		419,190
Revolving Loans - Amortized Cost Basis
Total	247,474		247,474		115,823
Total
Total	611,163		611,163		535,013
Long-Term Standby Purchase Commitments and Guaranteed Securities | Special mention | Agricultural Finance
Year One
Total	0		0		0
Year Two
Total	5,963		5,963		71
Year Three
Total	12,941		12,941		2,466
Year Four
Total	14,561		14,561		872
Year Five
Total	6,926		6,926		531
Prior
Total	46,864		46,864		44,631
Revolving Loans - Amortized Cost Basis
Total	12,134		12,134		8,565
Total
Total	99,389		99,389		57,136
Long-Term Standby Purchase Commitments and Guaranteed Securities | Special mention | Rural Infrastructure Finance
Year One
Total	0		0		0
Year Two
Total	0		0		0
Year Three
Total	0		0		0
Year Four
Total	0		0		0
Year Five
Total	0		0		0
Prior
Total	0		0		0
Revolving Loans - Amortized Cost Basis
Total	0		0		0
Total
Total	0		0		0
Long-Term Standby Purchase Commitments and Guaranteed Securities | Substandard | Agricultural Finance
Year One
Total	0		0		0
Year Two
Total	0		0		0
Year Three
Total	1,246		1,246		0
Year Four
Total	1,182		1,182		131
Year Five
Total	6,346		6,346		1,536
Prior
Total	25,839		25,839		26,328
Revolving Loans - Amortized Cost Basis
Total	1,214		1,214		5,091
Total
Total	35,827		35,827		33,086
Long-Term Standby Purchase Commitments and Guaranteed Securities | Substandard | Rural Infrastructure Finance
Year One
Total	0		0		0
Year Two
Total	0		0		0
Year Three
Total	0		0		0
Year Four
Total	0		0		0
Year Five
Total	0		0		0
Prior
Total	0		0		0
Revolving Loans - Amortized Cost Basis
Total	0		0		0
Total
Total	$ 0		$ 0		$ 0