Fair Value Disclosures - Fair Value Measurements, Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Assets:
Financial derivatives	$ 49,968	$ 6,081
Liabilities:
Financial derivatives	184,554	35,554
Investment securities:
Assets:
Available-for-sale, at fair value	4,401,879	$ 3,836,391
Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	$ 6,974,002
Level 3
Liabilities:
Percent of level three fair value assets and liabilities	26.00%	25.00%
Financial instruments level three percent	60.00%	62.00%
Recurring
Assets:
Financial derivatives	$ 49,968	$ 6,081
Guarantee Asset	4,692	6,237
Total Assets at fair value	11,432,392	10,181,669
Liabilities:
Financial derivatives	184,554	35,554
Total Liabilities at fair value	184,554	35,554
Recurring \| USDA Securities:
Assets:
Trading	1,851	4,401
Recurring \| Investment securities:
Assets:
Available-for-sale, at fair value	4,401,879	3,836,391
Recurring \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	6,974,002	6,328,559
Recurring \| Level 1
Assets:
Financial derivatives	536	73
Guarantee Asset	0	0
Total Assets at fair value	1,180,940	1,179,542
Liabilities:
Financial derivatives	18	0
Total Liabilities at fair value	18	0
Recurring \| Level 1 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 1 \| Investment securities:
Assets:
Available-for-sale, at fair value	1,180,404	1,179,469
Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	0	0
Recurring \| Level 2
Assets:
Financial derivatives	49,432	6,008
Guarantee Asset	0	0
Total Assets at fair value	3,251,664	2,643,676
Liabilities:
Financial derivatives	184,536	35,554
Total Liabilities at fair value	184,536	35,554
Recurring \| Level 2 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 2 \| Investment securities:
Assets:
Available-for-sale, at fair value	3,202,232	2,637,668
Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	0	0
Recurring \| Level 3
Assets:
Financial derivatives	0	0
Guarantee Asset	4,692	6,237
Total Assets at fair value	6,999,788	6,358,451
Liabilities:
Financial derivatives	0	0
Total Liabilities at fair value	0	0
Recurring \| Level 3 \| USDA Securities:
Assets:
Trading	1,851	4,401
Recurring \| Level 3 \| Investment securities:
Assets:
Available-for-sale, at fair value	19,243	19,254
Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	6,974,002	6,328,559
Fair Value, Nonrecurring
Assets:
Mortgage Servicing Rights		2,681
Total Assets at fair value		2,681
Fair Value, Nonrecurring \| Level 1
Assets:
Mortgage Servicing Rights		0
Total Assets at fair value		0
Fair Value, Nonrecurring \| Level 2
Assets:
Mortgage Servicing Rights		0
Total Assets at fair value		0
Fair Value, Nonrecurring \| Level 3
Assets:
Mortgage Servicing Rights		2,681
Total Assets at fair value		2,681
AgVantage Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	6,965,761	6,316,145
AgVantage Securities \| Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	0	0
AgVantage Securities \| Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	0	0
AgVantage Securities \| Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	6,965,761	6,316,145
Farmer Mac Guaranteed USDA Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	8,241	12,414
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	0	0
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	0	0
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	8,241	12,414
USDA Securities \| Recurring \| USDA Securities:
Assets:
Trading	1,851	4,401
USDA Securities \| Recurring \| Level 1 \| USDA Securities:
Assets:
Trading	0	0
USDA Securities \| Recurring \| Level 2 \| USDA Securities:
Assets:
Trading	0	0
USDA Securities \| Recurring \| Level 3 \| USDA Securities:
Assets:
Trading	1,851	4,401
Floating Interest Rate \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Available-for-sale, at fair value	19,243	19,254
Floating Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	2,360,528	2,178,831
Floating Interest Rate \| Recurring \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Available-for-sale, at fair value	19,243	19,254
Floating Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	2,360,528	2,178,831
Floating Interest Rate \| Recurring \| Level 1 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Available-for-sale, at fair value	0	0
Floating Interest Rate \| Recurring \| Level 1 \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	0	0
Floating Interest Rate \| Recurring \| Level 2 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Available-for-sale, at fair value	0	0
Floating Interest Rate \| Recurring \| Level 2 \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	2,360,528	2,178,831
Floating Interest Rate \| Recurring \| Level 3 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Available-for-sale, at fair value	19,243	19,254
Floating Interest Rate \| Recurring \| Level 3 \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	0	0
Fixed Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	841,704	458,837
Fixed Interest Rate \| Fixed rate U.S. Treasuries
Assets:
Available-for-sale, at fair value	1,180,404	1,179,469
Fixed Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	841,704	458,837
Fixed Interest Rate \| Recurring \| Fixed rate U.S. Treasuries
Assets:
Available-for-sale, at fair value	1,180,404	1,179,469
Fixed Interest Rate \| Recurring \| Level 1 \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	0	0
Fixed Interest Rate \| Recurring \| Level 1 \| Fixed rate U.S. Treasuries
Assets:
Available-for-sale, at fair value	1,180,404	1,179,469
Fixed Interest Rate \| Recurring \| Level 2 \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	841,704	458,837
Fixed Interest Rate \| Recurring \| Level 2 \| Fixed rate U.S. Treasuries
Assets:
Available-for-sale, at fair value	0	0
Fixed Interest Rate \| Recurring \| Level 3 \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	0	0
Fixed Interest Rate \| Recurring \| Level 3 \| Fixed rate U.S. Treasuries
Assets:
Available-for-sale, at fair value	$ 0	$ 0

Fair Value, Assets and Liabilities Fair Value as Percent of Total Assets

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Fair Value, Assets and Liabilities, Fair Value as Percent of Total Financial Instruments Measured at Fair Value

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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