BUSINESS SEGMENT REPORTING (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment	7
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	$ 327,547	$ 270,940	$ 221,951
Guarantee and commitment fees	16,712	13,040	12,669
Gains on sale of mortgage loans	0	0	6,539
Other income/(expense)	7,077	25,131	2,531
Total revenues	351,336	309,111	243,690
Release of/(provision for) losses	(858)	(1,323)	860
(Provision for)/release of reserve for losses	(278)	517	1,327
Operating expenses	(97,099)	(82,626)	(73,416)
Total non-interest expense	(97,377)	(82,109)	(72,089)
Core earnings before income taxes	253,101	225,679	172,461
Income tax (expense)/benefit	(53,098)	(47,535)	(36,372)
Core earnings before preferred stock dividends	200,003	178,144	136,089
Preferred stock dividends	(27,165)	(27,165)	(24,677)
Segment core earnings/(losses)	172,838	150,979	111,412
Total Assets	29,524,382	27,333,110	25,121,009
Total on- and off-balance sheet program assets at principal balance	28,471,024	25,922,082	23,614,463
Reconciling Adjustments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	0	0	0
Less: reconciling adjustments	567	15,411	1,283
Net effective spread	567	15,411	1,283
Guarantee and commitment fees	(2,216)	(5,104)	(4,864)
Gains on sale of mortgage loans			0
Other income/(expense)	3,778	23,447	851
Total revenues	2,129	33,754	(2,730)
Release of/(provision for) losses	0	0	0
(Provision for)/release of reserve for losses	0	0	0
Operating expenses	0	0	0
Total non-interest expense	0	0	0
Core earnings before income taxes	2,129	33,754	(2,730)
Income tax (expense)/benefit	(447)	(7,089)	572
Core earnings before preferred stock dividends	1,682	26,665	(2,158)
Preferred stock dividends	0	0	0
Segment core earnings/(losses)	1,682	26,665	(2,158)
Total Assets	0	0	0
Total on- and off-balance sheet program assets at principal balance	$ 0	0	0
Agricultural Finance
Segment Reporting [Abstract]
Number of operating segments | segment	2
Segment Reporting Information, Profit (Loss) [Abstract]
Release of/(provision for) losses	$ (100)	(3,400)	1,400
(Provision for)/release of reserve for losses	(652)	249	1,029
Farm & Ranch | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	137,079	133,218	118,289
Less: reconciling adjustments	(4,179)	(4,161)	(4,753)
Net effective spread	132,900	129,057	113,536
Guarantee and commitment fees	17,415	16,718	16,178
Gains on sale of mortgage loans			6,539
Other income/(expense)	2,952	1,420	1,966
Total revenues	153,267	147,195	138,219
Release of/(provision for) losses	145	(1,463)	1,574
(Provision for)/release of reserve for losses	(652)	247	1,034
Operating expenses	0	(819)	0
Total non-interest expense	(652)	(572)	1,034
Core earnings before income taxes	152,760	145,160	140,827
Income tax (expense)/benefit	(32,079)	(30,482)	(29,574)
Core earnings before preferred stock dividends	120,681	114,678	111,253
Preferred stock dividends	0	0	0
Segment core earnings/(losses)	120,681	114,678	111,253
Total Assets	15,052,606	14,623,596	13,112,193
Total on- and off-balance sheet program assets at principal balance	18,808,801	17,728,792	16,094,640
Corporate AgFinance | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	31,224	29,209	27,081
Less: reconciling adjustments	0	0	0
Net effective spread	31,224	29,209	27,081
Guarantee and commitment fees	283	139	48
Gains on sale of mortgage loans			0
Other income/(expense)	35	261	0
Total revenues	31,542	29,609	27,129
Release of/(provision for) losses	(207)	(2,136)	(210)
(Provision for)/release of reserve for losses	0	0	0
Operating expenses	0	0	0
Total non-interest expense	0	0	0
Core earnings before income taxes	31,335	27,473	26,919
Income tax (expense)/benefit	(6,581)	(5,768)	(5,653)
Core earnings before preferred stock dividends	24,754	21,705	21,266
Preferred stock dividends	0	0	0
Segment core earnings/(losses)	24,754	21,705	21,266
Total Assets	1,566,906	1,541,151	1,507,848
Total on- and off-balance sheet program assets at principal balance	1,693,979	1,603,507	1,537,834
Rural Infrastructure Finance
Segment Reporting Information, Profit (Loss) [Abstract]
Release of/(provision for) losses	(800)	2,300	(500)
(Provision for)/release of reserve for losses	374	268	298
Rural  Utilities | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	25,187	16,175	8,224
Less: reconciling adjustments	(168)	(103)	(157)
Net effective spread	25,019	16,072	8,067
Guarantee and commitment fees	1,133	1,238	1,287
Gains on sale of mortgage loans			0
Other income/(expense)	0	0	5
Total revenues	26,152	17,310	9,359
Release of/(provision for) losses	(581)	2,751	(291)
(Provision for)/release of reserve for losses	374	270	293
Operating expenses	0	0	0
Total non-interest expense	374	270	293
Core earnings before income taxes	25,945	20,331	9,361
Income tax (expense)/benefit	(5,449)	(4,268)	(1,965)
Core earnings before preferred stock dividends	20,496	16,063	7,396
Preferred stock dividends	0	0	0
Segment core earnings/(losses)	20,496	16,063	7,396
Total Assets	7,002,620	5,867,517	5,344,707
Total on- and off-balance sheet program assets at principal balance	7,480,723	6,359,613	5,895,226
Renewable Energy | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	4,648	2,483	1,219
Less: reconciling adjustments	0	0	0
Net effective spread	4,648	2,483	1,219
Guarantee and commitment fees	97	49	20
Gains on sale of mortgage loans			0
Other income/(expense)	0	0	0
Total revenues	4,745	2,532	1,239
Release of/(provision for) losses	(219)	(494)	(198)
(Provision for)/release of reserve for losses	0	0	0
Operating expenses	0	0	0
Total non-interest expense	0	0	0
Core earnings before income taxes	4,526	2,038	1,041
Income tax (expense)/benefit	(951)	(428)	(219)
Core earnings before preferred stock dividends	3,575	1,610	822
Preferred stock dividends	0	0	0
Segment core earnings/(losses)	3,575	1,610	822
Total Assets	443,772	219,609	87,553
Total on- and off-balance sheet program assets at principal balance	487,521	230,170	86,763
Funding | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	128,415	96,613	66,581
Less: reconciling adjustments	3,594	(11,147)	3,627
Net effective spread	132,009	85,466	70,208
Guarantee and commitment fees	0	0	0
Gains on sale of mortgage loans			0
Other income/(expense)	3	0	0
Total revenues	132,012	85,466	70,208
Release of/(provision for) losses	0	0	0
(Provision for)/release of reserve for losses	0	0	0
Operating expenses	0	0	0
Total non-interest expense	0	0	0
Core earnings before income taxes	132,012	85,466	70,208
Income tax (expense)/benefit	(27,721)	(17,949)	(14,744)
Core earnings before preferred stock dividends	104,291	67,517	55,464
Preferred stock dividends	0	0	0
Segment core earnings/(losses)	104,291	67,517	55,464
Total Assets	0	0	0
Total on- and off-balance sheet program assets at principal balance	0	0	0
Investments | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	994	(6,758)	557
Less: reconciling adjustments	186	0	0
Net effective spread	1,180	(6,758)	557
Guarantee and commitment fees	0	0	0
Gains on sale of mortgage loans			0
Other income/(expense)	29	0	0
Total revenues	1,209	(6,758)	557
Release of/(provision for) losses	4	19	(15)
(Provision for)/release of reserve for losses	0	0	0
Operating expenses	0	0	0
Total non-interest expense	0	0	0
Core earnings before income taxes	1,213	(6,739)	542
Income tax (expense)/benefit	(255)	1,416	(114)
Core earnings before preferred stock dividends	958	(5,323)	428
Preferred stock dividends	0	0	0
Segment core earnings/(losses)	958	(5,323)	428
Total Assets	5,342,089	4,806,010	5,012,827
Total on- and off-balance sheet program assets at principal balance	0	0	0
Corporate | Operating Segments
Segment Reporting Information, Profit (Loss) [Abstract]
Net interest income	0	0	0
Less: reconciling adjustments	0	0	0
Net effective spread	0	0	0
Guarantee and commitment fees	0	0	0
Gains on sale of mortgage loans			0
Other income/(expense)	280	3	(291)
Total revenues	280	3	(291)
Release of/(provision for) losses	0	0	0
(Provision for)/release of reserve for losses	0	0	0
Operating expenses	(97,099)	(81,807)	(73,416)
Total non-interest expense	(97,099)	(81,807)	(73,416)
Core earnings before income taxes	(96,819)	(81,804)	(73,707)
Income tax (expense)/benefit	20,385	17,033	15,325
Core earnings before preferred stock dividends	(76,434)	(64,771)	(58,382)
Preferred stock dividends	(27,165)	(27,165)	(24,677)
Segment core earnings/(losses)	(103,599)	(91,936)	(83,059)
Total Assets	116,389	275,227	55,881
Total on- and off-balance sheet program assets at principal balance	$ 0	$ 0	$ 0