FINANCIAL DERIVATIVES - Schedule of Net Income/(Expense) Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Derivative Instruments, Gain (Loss) [Line Items]
Interest Income Investments and Cash Equivalents	$ 93,398	$ 88,879	$ 265,691	$ 258,341
Interest Income Loans	198,459	162,247	555,262	459,932
Total Interest Expense	(316,864)	(320,937)	(909,564)	(947,252)
Gains (losses) on financial derivatives	(1,062)	(1,934)	(3,618)	(1,654)
Designated as hedge
Derivative Instruments, Gain (Loss) [Line Items]
Interest Income Investments and Cash Equivalents	93,398	88,879	265,691	258,341
Interest Income Farmer Mac Guaranteed Securities and USDA Securities	123,484	156,602	374,824	489,478
Interest Income Loans	198,459	162,247	555,262	459,932
Total Interest Expense	(316,864)	(320,937)	(909,564)	(947,252)
Gains (losses) on financial derivatives	(1,062)	(1,934)	(3,618)	(1,654)
Total	97,415	84,857	282,595	258,845
Designated as hedge | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on hedged items	(9,118)	(22,621)	(34,835)	(78,426)
Premium/discount amortization recognized on hedged items	109	(65)	(47)	(601)
Gains/(losses) on fair value hedging relationships, recognized on hedged items	10,860	137,139	122,647	(14,540)
(Losses)/gains on fair value hedging relationships	(137)	205	3,671	5,811
Designated as hedge | Cash flow hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Premium/discount amortization recognized on hedged items	(22)	(14)	(60)	(42)
Interest settlements reclassified from AOCI into net income on derivatives	3,593	5,338	11,163	16,162
Recognized on hedged items	(5,837)	(7,918)	(18,290)	(24,023)
Expense recognized on cash flow hedges	(2,266)	(2,594)	(7,187)	(7,903)
Designated as hedge | Interest Income Investments and Cash Equivalents | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on hedged items	14,558	11,476	41,789	31,734
Premium/discount amortization recognized on hedged items	690	623	1,917	1,555
Gains/(losses) on fair value hedging relationships, recognized on hedged items	7,376	60,915	60,625	30,032
(Losses)/gains on fair value hedging relationships	(208)	116	(228)	483
Designated as hedge | Interest Income Investments and Cash Equivalents | Cash flow hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Premium/discount amortization recognized on hedged items	0	0	0	0
Interest settlements reclassified from AOCI into net income on derivatives	0	0	0	0
Recognized on hedged items	0	0	0	0
Expense recognized on cash flow hedges	0	0	0	0
Designated as hedge | Interest Income Farmer Mac Guaranteed Securities and USDA Securities | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on hedged items	57,249	54,513	169,792	158,869
Premium/discount amortization recognized on hedged items	0	0	0	0
Gains/(losses) on fair value hedging relationships, recognized on hedged items	19,248	189,141	139,035	101,890
(Losses)/gains on fair value hedging relationships	(285)	(557)	(461)	704
Designated as hedge | Interest Income Farmer Mac Guaranteed Securities and USDA Securities | Cash flow hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Premium/discount amortization recognized on hedged items	0	0	0	0
Interest settlements reclassified from AOCI into net income on derivatives	0	0	0	0
Recognized on hedged items	0	0	0	0
Expense recognized on cash flow hedges	0	0	0	0
Designated as hedge | Interest Income Loans | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on hedged items	21,659	17,544	60,261	50,847
Premium/discount amortization recognized on hedged items	0	0	0	0
Gains/(losses) on fair value hedging relationships, recognized on hedged items	10,436	98,015	64,277	38,842
(Losses)/gains on fair value hedging relationships	(428)	(449)	832	1,746
Designated as hedge | Interest Income Loans | Cash flow hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Premium/discount amortization recognized on hedged items	0	0	0	0
Interest settlements reclassified from AOCI into net income on derivatives	0	0	0	0
Recognized on hedged items	0	0	0	0
Expense recognized on cash flow hedges	0	0	0	0
Designated as hedge | Total Interest Expense | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on hedged items	(102,584)	(106,154)	(306,677)	(319,876)
Premium/discount amortization recognized on hedged items	(581)	(688)	(1,964)	(2,156)
Gains/(losses) on fair value hedging relationships, recognized on hedged items	(26,200)	(210,932)	(141,290)	(185,304)
(Losses)/gains on fair value hedging relationships	784	1,095	3,528	2,878
Designated as hedge | Total Interest Expense | Cash flow hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Premium/discount amortization recognized on hedged items	(22)	(14)	(60)	(42)
Interest settlements reclassified from AOCI into net income on derivatives	3,593	5,338	11,163	16,162
Recognized on hedged items	(5,837)	(7,918)	(18,290)	(24,023)
Expense recognized on cash flow hedges	(2,266)	(2,594)	(7,187)	(7,903)
Designated as hedge | Losses on financial derivatives | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on hedged items	0	0	0	0
Premium/discount amortization recognized on hedged items	0	0	0	0
Gains/(losses) on fair value hedging relationships, recognized on hedged items	0	0	0	0
(Losses)/gains on fair value hedging relationships	0	0	0	0
Designated as hedge | Losses on financial derivatives | Cash flow hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Premium/discount amortization recognized on hedged items	0	0	0	0
Interest settlements reclassified from AOCI into net income on derivatives	0	0	0	0
Recognized on hedged items	0	0	0	0
Expense recognized on cash flow hedges	0	0	0	0
Designated as hedge | Interest Rate Swap | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on derivatives	14,351	(1,654)	41,118	(26,016)
Income/(expense) related to interest settlements on fair value hedging relationships	5,342	(24,340)	6,236	(105,043)
Gains/(losses) on fair value hedging relationships, recognized on derivatives	(10,997)	(136,934)	(118,976)	20,351
Designated as hedge | Interest Rate Swap | Interest Income Investments and Cash Equivalents | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on derivatives	7,541	10,774	21,887	31,479
Income/(expense) related to interest settlements on fair value hedging relationships	22,789	22,873	65,593	64,768
Gains/(losses) on fair value hedging relationships, recognized on derivatives	(7,584)	(60,799)	(60,853)	(29,549)
Designated as hedge | Interest Rate Swap | Interest Income Farmer Mac Guaranteed Securities and USDA Securities | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on derivatives	23,004	39,127	66,809	118,593
Income/(expense) related to interest settlements on fair value hedging relationships	80,253	93,640	236,601	277,462
Gains/(losses) on fair value hedging relationships, recognized on derivatives	(19,533)	(189,698)	(139,496)	(101,186)
Designated as hedge | Interest Rate Swap | Interest Income Loans | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on derivatives	12,857	17,878	37,742	53,554
Income/(expense) related to interest settlements on fair value hedging relationships	34,516	35,422	98,003	104,401
Gains/(losses) on fair value hedging relationships, recognized on derivatives	(10,864)	(98,464)	(63,445)	(37,096)
Designated as hedge | Interest Rate Swap | Total Interest Expense | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on derivatives	(29,051)	(69,433)	(85,320)	(229,642)
Income/(expense) related to interest settlements on fair value hedging relationships	(132,216)	(176,275)	(393,961)	(551,674)
Gains/(losses) on fair value hedging relationships, recognized on derivatives	26,984	212,027	144,818	188,182
Designated as hedge | Interest Rate Swap | Losses on financial derivatives | Fair value hedges:
Derivative Instruments, Gain (Loss) [Line Items]
Recognized on derivatives	0	0	0	0
Income/(expense) related to interest settlements on fair value hedging relationships	0	0	0	0
Gains/(losses) on fair value hedging relationships, recognized on derivatives	0	0	0	0
No hedge designation
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	(1,062)	(1,934)	(3,618)	(1,654)
No hedge designation | Interest Income Investments and Cash Equivalents
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Interest Income Farmer Mac Guaranteed Securities and USDA Securities
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Interest Income Loans
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Total Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Losses on financial derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	(1,062)	(1,934)	(3,618)	(1,654)
No hedge designation | Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	474	(1,310)	(3,063)	(581)
Interest expense on interest rate swaps	(707)	(858)	(597)	(1,379)
No hedge designation | Interest Rate Swap | Interest Income Investments and Cash Equivalents
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
Interest expense on interest rate swaps	0	0	0	0
No hedge designation | Interest Rate Swap | Interest Income Farmer Mac Guaranteed Securities and USDA Securities
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
Interest expense on interest rate swaps	0	0	0	0
No hedge designation | Interest Rate Swap | Interest Income Loans
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
Interest expense on interest rate swaps	0	0	0	0
No hedge designation | Interest Rate Swap | Total Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
Interest expense on interest rate swaps	0	0	0	0
No hedge designation | Interest Rate Swap | Losses on financial derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	474	(1,310)	(3,063)	(581)
Interest expense on interest rate swaps	(707)	(858)	(597)	(1,379)
No hedge designation | Treasury futures
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	(829)	234	42	306
No hedge designation | Treasury futures | Interest Income Investments and Cash Equivalents
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Treasury futures | Interest Income Farmer Mac Guaranteed Securities and USDA Securities
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Treasury futures | Interest Income Loans
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Treasury futures | Total Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	0	0	0	0
No hedge designation | Treasury futures | Losses on financial derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on financial derivatives	$ (829)	$ 234	$ 42	$ 306