Fair Value Disclosures - Fair Value Measurements, Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Financial derivatives	$ 19,139	$ 16,123
Liabilities:
Financial derivatives	160,271	182,371
Investment securities:
Assets:
Fair Value	3,836,391	$ 3,853,692
Farmer Mac Guaranteed Securities
Assets:
Fair Value	$ 6,328,559
Level 3
Liabilities:
Percent of level three fair value assets and liabilities	25.00%	29.00%
Financial instruments level three percent	62.00%	65.00%
Recurring
Assets:
Financial derivatives	$ 19,139	$ 17,468
Guarantee Asset	6,237
Total Assets at fair value	10,194,727	10,825,556
Liabilities:
Financial derivatives	34,248	29,892
Total Liabilities at fair value	34,248	29,892
Recurring \| USDA Securities:
Assets:
Trading	4,401	6,695
Recurring \| Investment securities:
Assets:
Fair Value	3,836,391	3,853,692
Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	6,328,559	6,947,701
Recurring \| Level 1
Assets:
Financial derivatives	73	0
Guarantee Asset	0
Total Assets at fair value	1,179,542	1,467,951
Liabilities:
Financial derivatives	0	82
Total Liabilities at fair value	0	82
Recurring \| Level 1 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 1 \| Investment securities:
Assets:
Fair Value	1,179,469	1,467,951
Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
Recurring \| Level 2
Assets:
Financial derivatives	19,066	17,468
Guarantee Asset	0
Total Assets at fair value	2,656,734	2,384,038
Liabilities:
Financial derivatives	34,248	29,810
Total Liabilities at fair value	34,248	29,810
Recurring \| Level 2 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 2 \| Investment securities:
Assets:
Fair Value	2,637,668	2,366,570
Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
Recurring \| Level 3
Assets:
Financial derivatives	0	0
Guarantee Asset	6,237
Total Assets at fair value	6,358,451	6,973,567
Liabilities:
Financial derivatives	0	0
Total Liabilities at fair value	0	0
Recurring \| Level 3 \| USDA Securities:
Assets:
Trading	4,401	6,695
Recurring \| Level 3 \| Investment securities:
Assets:
Fair Value	19,254	19,171
Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	6,328,559	6,947,701
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:
Fair Value	6,316,145	6,947,701
AgVantage Securities \| Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
AgVantage Securities \| Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
AgVantage Securities \| Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	6,316,145	6,947,701
Farmer Mac Guaranteed USDA Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	12,414
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	12,414
USDA Securities \| Recurring \| USDA Securities:
Assets:
Trading	4,401	6,695
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	4,401	6,695
Floating Interest Rate \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,254	19,171
Floating Interest Rate \| Floating rate asset-backed securities
Assets:
Fair Value		6,231
Floating Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,178,831	2,360,026
Floating Interest Rate \| Recurring \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,254	19,171
Floating Interest Rate \| Recurring \| Floating rate asset-backed securities
Assets:
Fair Value		6,231
Floating Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,178,831	2,360,026
Floating Interest Rate \| Recurring \| Level 1 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	0	0
Floating Interest Rate \| Recurring \| Level 1 \| Floating rate asset-backed securities
Assets:
Fair Value		0
Floating Interest Rate \| Recurring \| Level 1 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	0	0
Floating Interest Rate \| Recurring \| Level 2 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	0	0
Floating Interest Rate \| Recurring \| Level 2 \| Floating rate asset-backed securities
Assets:
Fair Value		6,231
Floating Interest Rate \| Recurring \| Level 2 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,178,831	2,360,026
Floating Interest Rate \| Recurring \| Level 3 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,254	19,171
Floating Interest Rate \| Recurring \| Level 3 \| Floating rate asset-backed securities
Assets:
Fair Value		0
Floating Interest Rate \| Recurring \| Level 3 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	0	0
Fixed Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Fair Value	458,837	313
Fixed Interest Rate \| Fixed rate U.S. Treasuries
Assets:
Fair Value	1,179,469	1,467,951
Fixed Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Fair Value	458,837	313
Fixed Interest Rate \| Recurring \| Fixed rate U.S. Treasuries
Assets:
Fair Value	1,179,469	1,467,951
Fixed Interest Rate \| Recurring \| Level 1 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	0	0
Fixed Interest Rate \| Recurring \| Level 1 \| Fixed rate U.S. Treasuries
Assets:
Fair Value	1,179,469	1,467,951
Fixed Interest Rate \| Recurring \| Level 2 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	458,837	313
Fixed Interest Rate \| Recurring \| Level 2 \| Fixed rate U.S. Treasuries
Assets:
Fair Value	0	0
Fixed Interest Rate \| Recurring \| Level 3 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	0	0
Fixed Interest Rate \| Recurring \| Level 3 \| Fixed rate U.S. Treasuries
Assets:
Fair Value	$ 0	$ 0

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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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