Fair Value Disclosures - Fair Value Measurements, Recurring and Nonrecurring (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets:
Financial derivatives	$ 26,824	$ 37,409
Liabilities:
Financial derivatives	188,652	175,326
Investment Securities
Assets:
Fair Value	4,717,619	$ 4,579,564
Farmer Mac Guaranteed Securities
Assets:
Fair Value	$ 7,745,415
Level 3
Liabilities:
Percent of level three fair value assets and liabilities	28.00%	28.00%
Financial instruments level three percent	61.00%	62.00%
Recurring
Assets:
Financial derivatives	$ 26,824	$ 37,409
Guarantee Asset	4,331	4,467
Total Assets at fair value	12,495,537	12,230,433
Liabilities:
Financial derivatives	188,652	175,326
Total Liabilities at fair value	188,652	175,326
Recurring \| USDA Securities:
Assets:
Trading	1,348	1,767
Recurring \| Investment Securities
Assets:
Fair Value	4,717,619	4,579,564
Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	7,745,415	7,607,226
Recurring \| Level 1
Assets:
Financial derivatives	71	0
Guarantee Asset	0	0
Total Assets at fair value	895,264	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	895,193	1,119,611
Recurring \| Level 1 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	0	0
Recurring \| Level 2
Assets:
Financial derivatives	26,753	37,409
Guarantee Asset	0	0
Total Assets at fair value	3,830,147	3,478,335
Liabilities:
Financial derivatives	188,652	175,184
Total Liabilities at fair value	188,652	175,184
Recurring \| Level 2 \| USDA Securities:
Assets:
Trading	0	0
Recurring \| Level 2 \| Investment Securities
Assets:
Fair Value	3,803,394	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	4,331	4,467
Total Assets at fair value	7,770,126	7,632,487
Liabilities:
Financial derivatives	0	0
Total Liabilities at fair value	0	0
Recurring \| Level 3 \| USDA Securities:
Assets:
Trading	1,348	1,767
Recurring \| Level 3 \| Investment Securities
Assets:
Fair Value	19,032	19,027
Recurring \| Level 3 \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	7,745,415	7,607,226
AgVantage Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	7,737,810	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	7,737,810	7,599,379
Farmer Mac Guaranteed USDA Securities \| Recurring \| Farmer Mac Guaranteed Securities
Assets:
Fair Value	7,605	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	7,605	7,847
USDA Securities \| Recurring \| USDA Securities:
Assets:
Trading	1,348	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	1,348	1,767
Floating Interest Rate \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,032	19,027
Floating Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,442,610	2,392,540
Floating Interest Rate \| Fixed rate U.S. Treasuries
Assets:
Fair Value	49,998
Floating Interest Rate \| Recurring \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,032	19,027
Floating Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Fair Value	2,442,610	2,392,540
Floating Interest Rate \| Recurring \| Floating rate U.S. Treasuries
Assets:
Fair Value	49,998
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 1 \| Floating rate U.S. Treasuries
Assets:
Fair Value	49,998
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	2,442,610	2,392,540
Floating Interest Rate \| Recurring \| Level 2 \| Floating rate U.S. Treasuries
Assets:
Fair Value	0
Floating Interest Rate \| Recurring \| Level 3 \| Floating rate auction-rate certificates backed by Government guaranteed student loans
Assets:
Fair Value	19,032	19,027
Floating Interest Rate \| Recurring \| Level 3 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	0	0
Floating Interest Rate \| Recurring \| Level 3 \| Floating rate U.S. Treasuries
Assets:
Fair Value	0
Fixed Interest Rate \| Guaranteed mortgage-backed securities
Assets:
Fair Value	1,360,784	1,048,386
Fixed Interest Rate \| Fixed rate U.S. Treasuries
Assets:
Fair Value	845,195	1,119,611
Fixed Interest Rate \| Recurring \| Guaranteed mortgage-backed securities
Assets:
Fair Value	1,360,784	1,048,386
Fixed Interest Rate \| Recurring \| Fixed rate U.S. Treasuries
Assets:
Fair Value	845,195	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	845,195	1,119,611
Fixed Interest Rate \| Recurring \| Level 2 \| Guaranteed mortgage-backed securities
Assets:
Fair Value	1,360,784	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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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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