Fair Value Disclosures - Fair Value Measurements, Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Assets:
Financial derivatives	$ 25,099	$ 37,409
Liabilities:
Financial derivatives	166,963	175,326
Investment securities:
Assets:
Fair Value	4,647,464	$ 4,579,564
Farmer Mac Guaranteed Securities
Assets:
Fair Value	$ 8,225,454
Level 3
Liabilities:
Percent of level three fair value assets and liabilities	30.00%	28.00%
Financial instruments level three percent	63.00%	62.00%
Recurring
Assets:
Financial derivatives	$ 25,099	$ 37,409
Guarantee Asset	4,570	4,467
Total Assets at fair value	12,903,992	12,230,433
Liabilities:
Financial derivatives	166,963	175,326
Total Liabilities at fair value	166,963	175,326
Recurring \| USDA Securities:
Assets:
Trading	1,405	1,767
Recurring \| Investment securities:
Assets:
Fair Value	4,647,464	4,579,564
Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	8,225,454	7,607,226
Recurring \| Level 1
Assets:
Financial derivatives	614	0
Guarantee Asset	0	0
Total Assets at fair value	923,614	1,119,611
Liabilities:
Financial derivatives	0	142
Total Liabilities at fair value	0	142
Recurring \| Level 1 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 1 \| Investment securities:
Assets:
Fair Value	923,000	1,119,611
Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
Recurring \| Level 2
Assets:
Financial derivatives	24,485	37,409
Guarantee Asset	0	0
Total Assets at fair value	3,729,918	3,478,335
Liabilities:
Financial derivatives	166,963	175,184
Total Liabilities at fair value	166,963	175,184
Recurring \| Level 2 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 2 \| Investment securities:
Assets:
Fair Value	3,705,433	3,440,926
Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
Recurring \| Level 3
Assets:
Financial derivatives	0	0
Guarantee Asset	4,570	4,467
Total Assets at fair value	8,250,460	7,632,487
Liabilities:
Financial derivatives	0	0
Total Liabilities at fair value	0	0
Recurring \| Level 3 \| USDA Securities:
Assets:
Trading	1,405	1,767
Recurring \| Level 3 \| Investment securities:
Assets:
Fair Value	19,031	19,027
Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	8,225,454	7,607,226
AgVantage Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	8,217,420	7,599,379
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	8,217,420	7,599,379
Farmer Mac Guaranteed USDA Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	8,034	7,847
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 2 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
Farmer Mac Guaranteed USDA Securities \| Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	8,034	7,847
USDA Securities \| Recurring \| USDA Securities:
Assets:
Trading	1,405	1,767
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	1,405	1,767
Floating Interest Rate \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,031	19,027
Floating Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,450,585	2,392,540
Floating Interest Rate \| Recurring \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,031	19,027
Floating Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,450,585	2,392,540
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 \| 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 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,450,585	2,392,540
Floating Interest Rate \| Recurring \| Level 3 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,031	19,027
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	1,254,848	1,048,386
Fixed Interest Rate \| Fixed rate U.S. Treasuries
Assets:
Fair Value	923,000	1,119,611
Fixed Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Fair Value	1,254,848	1,048,386
Fixed Interest Rate \| Recurring \| Fixed rate U.S. Treasuries
Assets:
Fair Value	923,000	1,119,611
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	923,000	1,119,611
Fixed Interest Rate \| Recurring \| Level 2 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	1,254,848	1,048,386
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

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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