Fair Value Disclosures - Summary of Carrying Value and Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial derivatives	$ 7,027	$ 4,177
Guarantee and commitment fees receivable:	40,160	39,462
Derivative Liability	46,769	38,217
Guarantee and commitment obligation	38,253	37,925
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,516,536	1,363,387
Loans	3,756,534	3,520,075
Financial derivatives	7,027	4,177
Debt securities of consolidated trusts held by third parties	612,994	424,214
Derivative Liability	94,880	84,844
Reported Value Measurement [Member] \| Investment Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities	2,032,179	1,939,188
Reported Value Measurement [Member] \| Farmer Mac Guaranteed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities	5,432,823	5,453,901
Reported Value Measurement [Member] \| USDA Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities	1,886,358	1,771,532
Reported Value Measurement [Member] \| Long-Term Standby Purchase Commitments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Guarantee and commitment fees receivable:	29,972	27,807
Guarantee and commitment obligation	29,071	26,843
Reported Value Measurement [Member] \| Farmer Mac Guaranteed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Guarantee and commitment fees receivable:	10,188	11,655
Guarantee and commitment obligation	9,182	11,082
Reported Value Measurement [Member] \| Due within one year [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes payable:	8,280,087	7,353,953
Reported Value Measurement [Member] \| Long-term Debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes payable:	5,217,307	5,471,186
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,516,536	1,363,387
Loans	3,793,936	3,547,424
Financial derivatives	7,027	4,177
Debt securities of consolidated trusts held by third parties	613,539	423,085
Derivative Liability	94,880	84,844
Estimate of Fair Value Measurement [Member] \| Investment Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities	2,032,179	1,939,188
Estimate of Fair Value Measurement [Member] \| Farmer Mac Guaranteed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities	5,447,960	5,459,857
Estimate of Fair Value Measurement [Member] \| USDA Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable Securities	1,886,358	1,771,532
Estimate of Fair Value Measurement [Member] \| Long-Term Standby Purchase Commitments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Guarantee and commitment fees receivable:	31,143	29,095
Guarantee and commitment obligation	30,242	28,130
Estimate of Fair Value Measurement [Member] \| Farmer Mac Guaranteed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Guarantee and commitment fees receivable:	10,110	11,876
Guarantee and commitment obligation	9,104	11,303
Estimate of Fair Value Measurement [Member] \| Due within one year [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes payable:	8,288,217	7,357,770
Estimate of Fair Value Measurement [Member] \| Long-term Debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes payable:	$ 5,305,185	$ 5,556,570

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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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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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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-Section 02

-Paragraph 19, 20, 22

-Article 5

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