Business Segment Reporting - Narrative (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Total notes payable	$ 12,825,139,000us-gaap_DebtAndCapitalLeaseObligations	$ 12,339,950,000us-gaap_DebtAndCapitalLeaseObligations
Farmer Mac II LLC [Member]
Segment Reporting Information [Line Items]
Assets, Fair Value Disclosure	1,800,000,000
Total notes payable	470,000,000
Preferred Stock outstanding	250,000,000
Common Stock outstanding	$ 1,000,000,000

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Value of all classes of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares exclude common shares repurchased by the entity and held as treasury shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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