BUSINESS SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) segment	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment	7
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	$ 86,368	$ 79,058
Guarantee and commitment fees	3,917	3,933
Other income/(expense)	3,328	1,625
Total revenues	93,613	84,616
Release of/(provision for) losses	1,801	(547)
Release of/(provision for) reserve for losses	69	(203)
Operating expenses	(27,237)	(23,713)
Total non-interest expense	(27,168)	(23,916)
Core earnings before income taxes	68,246	60,153
Income tax (expense)/benefit	(14,500)	(13,118)
Core earnings before preferred stock dividends	53,746	47,035
Preferred stock dividends	(6,791)	(6,791)
Segment core earnings/(losses)	46,955	40,244
Total Assets	29,772,191	27,939,947	$ 29,524,382
Total on- and off-balance sheet program assets at principal balance	28,847,230	26,484,118
Reconciling Adjustments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	0	0
Less: reconciling adjustments	3,324	1,885
Net effective spread	3,324	1,885
Guarantee and commitment fees	(1,065)	(721)
Other income/(expense)	2,251	558
Total revenues	4,510	1,722
Release of/(provision for) losses	0	0
Release of/(provision for) reserve for losses	0	0
Operating expenses	0	0
Total non-interest expense	0	0
Core earnings before income taxes	4,510	1,722
Income tax (expense)/benefit	(947)	(362)
Core earnings before preferred stock dividends	3,563	1,360
Preferred stock dividends	0	0
Segment core earnings/(losses)	3,563	1,360
Total Assets	0	0
Total on- and off-balance sheet program assets at principal balance	$ 0	0
Agricultural Finance
Segment Reporting [Abstract]
Number of operating segments | segment	2
Segment Reporting Information, Profit (Loss) [Abstract]
Release of/(provision for) reserve for losses	$ 64	(577)
Farm & Ranch | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	33,889	33,511
Less: reconciling adjustments	(1,046)	(1,046)
Net effective spread	32,843	32,465
Guarantee and commitment fees	4,484	4,292
Other income/(expense)	995	1,067
Total revenues	38,322	37,824
Release of/(provision for) losses	(561)	128
Release of/(provision for) reserve for losses	64	(577)
Operating expenses	0	0
Total non-interest expense	64	(577)
Core earnings before income taxes	37,825	37,375
Income tax (expense)/benefit	(7,943)	(7,849)
Core earnings before preferred stock dividends	29,882	29,526
Preferred stock dividends	0	0
Segment core earnings/(losses)	29,882	29,526
Total Assets	15,240,436	14,549,275
Total on- and off-balance sheet program assets at principal balance	18,900,906	17,685,961
Corporate AgFinance | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	7,971	7,148
Less: reconciling adjustments	0	0
Net effective spread	7,971	7,148
Guarantee and commitment fees	87	53
Other income/(expense)	12	0
Total revenues	8,070	7,201
Release of/(provision for) losses	378	(4,301)
Release of/(provision for) reserve for losses	0	0
Operating expenses	0	0
Total non-interest expense	0	0
Core earnings before income taxes	8,448	2,900
Income tax (expense)/benefit	(1,774)	(609)
Core earnings before preferred stock dividends	6,674	2,291
Preferred stock dividends	0	0
Segment core earnings/(losses)	6,674	2,291
Total Assets	1,637,460	1,515,976
Total on- and off-balance sheet program assets at principal balance	1,766,294	1,599,982
Rural Infrastructure Finance
Segment Reporting Information, Profit (Loss) [Abstract]
Release of/(provision for) reserve for losses	5	374
Rural  Utilities | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	7,265	5,540
Less: reconciling adjustments	(33)	(33)
Net effective spread	7,232	5,507
Guarantee and commitment fees	349	281
Other income/(expense)	0	0
Total revenues	7,581	5,788
Release of/(provision for) losses	3,017	3,484
Release of/(provision for) reserve for losses	5	374
Operating expenses	0	0
Total non-interest expense	5	374
Core earnings before income taxes	10,603	9,646
Income tax (expense)/benefit	(2,227)	(2,026)
Core earnings before preferred stock dividends	8,376	7,620
Preferred stock dividends	0	0
Segment core earnings/(losses)	8,376	7,620
Total Assets	7,003,165	6,444,264
Total on- and off-balance sheet program assets at principal balance	7,437,723	6,889,682
Renewable Energy | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	2,049	858
Less: reconciling adjustments	0	0
Net effective spread	2,049	858
Guarantee and commitment fees	62	28
Other income/(expense)	0	0
Total revenues	2,111	886
Release of/(provision for) losses	(1,034)	138
Release of/(provision for) reserve for losses	0	0
Operating expenses	0	0
Total non-interest expense	0	0
Core earnings before income taxes	1,077	1,024
Income tax (expense)/benefit	(226)	(215)
Core earnings before preferred stock dividends	851	809
Preferred stock dividends	0	0
Segment core earnings/(losses)	851	809
Total Assets	578,709	286,824
Total on- and off-balance sheet program assets at principal balance	742,307	308,493
Funding | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	34,719	32,544
Less: reconciling adjustments	(2,245)	(806)
Net effective spread	32,474	31,738
Guarantee and commitment fees	0	0
Other income/(expense)	0	0
Total revenues	32,474	31,738
Release of/(provision for) losses	0	0
Release of/(provision for) reserve for losses	0	0
Operating expenses	0	0
Total non-interest expense	0	0
Core earnings before income taxes	32,474	31,738
Income tax (expense)/benefit	(6,819)	(6,665)
Core earnings before preferred stock dividends	25,655	25,073
Preferred stock dividends	0	0
Segment core earnings/(losses)	25,655	25,073
Total Assets	0	0
Total on- and off-balance sheet program assets at principal balance	0	0
Investments | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	475	(543)
Less: reconciling adjustments	0	0
Net effective spread	475	(543)
Guarantee and commitment fees	0	0
Other income/(expense)	4	0
Total revenues	479	(543)
Release of/(provision for) losses	1	4
Release of/(provision for) reserve for losses	0	0
Operating expenses	0	0
Total non-interest expense	0	0
Core earnings before income taxes	480	(539)
Income tax (expense)/benefit	(101)	113
Core earnings before preferred stock dividends	379	(426)
Preferred stock dividends	0	0
Segment core earnings/(losses)	379	(426)
Total Assets	5,190,082	4,998,854
Total on- and off-balance sheet program assets at principal balance	0	0
Corporate | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	0	0
Less: reconciling adjustments	0	0
Net effective spread	0	0
Guarantee and commitment fees	0	0
Other income/(expense)	66	0
Total revenues	66	0
Release of/(provision for) losses	0	0
Release of/(provision for) reserve for losses	0	0
Operating expenses	(27,237)	(23,713)
Total non-interest expense	(27,237)	(23,713)
Core earnings before income taxes	(27,171)	(23,713)
Income tax (expense)/benefit	5,537	4,495
Core earnings before preferred stock dividends	(21,634)	(19,218)
Preferred stock dividends	(6,791)	(6,791)
Segment core earnings/(losses)	(28,425)	(26,009)
Total Assets	122,339	144,754
Total on- and off-balance sheet program assets at principal balance	$ 0	$ 0