Fair Value Disclosures - Summary of Carrying Value and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial derivatives	$ 13,453	$ 16,123
Guarantee and commitment fees receivable	35,878	37,113
Financial derivatives	169,814	182,371
Guarantee and commitment obligation	34,403	35,535
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,012,541	1,033,941
Loans	9,178,052	9,167,525
Financial derivatives	18,370	17,468
Guarantee and commitment fees receivable	34,114	34,115
Notes payable	21,678,738	22,130,263
Debt securities of consolidated trusts held by third parties	1,264,293	1,390,330
Financial derivatives	28,345	29,892
Guarantee and commitment obligation	32,639	32,537
Fair Value \| Investment securities:
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	3,856,619	3,899,925
Fair Value \| Farmer Mac Guaranteed Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	7,937,251	8,148,691
Fair Value \| USDA Securities:
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	2,624,456	2,637,509
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,012,541	1,033,941
Loans	8,501,630	8,535,146
Financial derivatives	18,370	17,468
Guarantee and commitment fees receivable	35,878	37,113
Notes payable	21,560,310	21,848,917
Debt securities of consolidated trusts held by third parties	1,188,521	1,323,786
Financial derivatives	28,345	29,892
Guarantee and commitment obligation	34,403	35,535
Carrying Amount \| Investment securities:
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	3,855,067	3,898,724
Carrying Amount \| Farmer Mac Guaranteed Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	7,922,001	8,123,493
Carrying Amount \| USDA Securities:
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	$ 2,495,078	$ 2,480,321

Marketable Securities, Fair Value Disclosure

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Variable Interest Entity, Consolidated, Fair Value Disclosure, Liabilities

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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The carrying amount of the contractual right to receive fees, as compensation in exchange for providing a guarantee to a third party, over life of the guarantee.

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This item represents a non-contingent liability for the fair value of an obligation to stand ready to perform over the term of a guaranty issued in the event that specified triggering events or conditions occur.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value portion of notes payable.

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