Fair Value Disclosures - Fair Value Measurements, Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Assets:
Financial derivatives	$ 30,011	$ 19,139
Investment securities:
Assets:
Available-for-sale, at fair value	4,246,012	$ 3,836,391
Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	$ 6,450,212
Level 3
Liabilities:
Percent of level three fair value assets and liabilities	25.00%	25.00%
Financial instruments level three percent	60.00%	62.00%
Recurring
Assets:
Financial derivatives	$ 30,011	$ 19,139
Guarantee Asset	5,636	6,237
Total Assets at fair value	10,734,146	10,194,727
Liabilities:
Financial derivatives	127,983	34,248
Total Liabilities at fair value	127,983	34,248
Recurring \| USDA Securities:
Assets:
Trading	2,275	4,401
Recurring \| Investment securities:
Assets:
Available-for-sale, at fair value	4,246,012	3,836,391
Recurring \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	6,450,212	6,328,559
Recurring \| Level 1
Assets:
Financial derivatives	350	73
Guarantee Asset	0	0
Total Assets at fair value	1,177,164	1,179,542
Liabilities:
Financial derivatives	1,046	0
Total Liabilities at fair value	1,046	0
Recurring \| Level 1 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 1 \| Investment securities:
Assets:
Available-for-sale, at fair value	1,176,814	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	29,661	19,066
Guarantee Asset	0	0
Total Assets at fair value	3,079,798	2,656,734
Liabilities:
Financial derivatives	126,937	34,248
Total Liabilities at fair value	126,937	34,248
Recurring \| Level 2 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 2 \| Investment securities:
Assets:
Available-for-sale, at fair value	3,050,137	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	5,636	6,237
Total Assets at fair value	6,477,184	6,358,451
Liabilities:
Financial derivatives	0	0
Total Liabilities at fair value	0	0
Recurring \| Level 3 \| USDA Securities:
Assets:
Trading	2,275	4,401
Recurring \| Level 3 \| Investment securities:
Assets:
Available-for-sale, at fair value	19,061	19,254
Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	6,450,212	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	6,440,396	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	6,440,396	6,316,145
Farmer Mac Guaranteed USDA Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Available-for-sale, at fair value	9,816	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	9,816	12,414
USDA Securities \| Recurring \| USDA Securities:
Assets:
Trading	2,275	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	2,275	4,401
Floating Interest Rate \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Available-for-sale, at fair value	19,061	19,254
Floating Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	2,372,459	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	19,061	19,254
Floating Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	2,372,459	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	2,372,459	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	19,061	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	677,678	458,837
Fixed Interest Rate \| Fixed rate U.S. Treasuries
Assets:
Available-for-sale, at fair value	1,176,814	1,179,469
Fixed Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	677,678	458,837
Fixed Interest Rate \| Recurring \| Fixed rate U.S. Treasuries
Assets:
Available-for-sale, at fair value	1,176,814	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	1,176,814	1,179,469
Fixed Interest Rate \| Recurring \| Level 2 \| Guaranteed mortgage-backed securities
Assets:
Available-for-sale, at fair value	677,678	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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