LOANS - Summary of Changes in Allowance for Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 37,785	$ 23,223
Provision for losses	4,310	1,750
Charge-offs	(2,175)	0
Recovery	0	83
Ending balance	39,920	25,056
Total Agricultural Finance loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Provision for losses		800
Farm & Ranch
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	9,400	5,132
Provision for losses	2,924	(61)
Charge-offs	0	0
Recovery	0	0
Ending balance	12,324	5,071
Farm & Ranch \| Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Provision for losses	3,100	700
Corporate AgFinance
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	6,631	5,379
Provision for losses	1,965	836
Charge-offs	(2,175)	0
Recovery	0	83
Ending balance	6,421	6,298
Corporate AgFinance \| Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Provision for losses	0	1,000
Infrastructure Finance loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	21,754	12,712
Provision for losses	(579)	975
Charge-offs	0	0
Recovery	0	0
Ending balance	21,175	13,687
Infrastructure Finance loans \| Collateral Pledged
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Provision for losses	$ 5,200	$ 0	$ 0

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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