Farmer Mac Guaranteed Securities and USDA Guaranteed Securities - Farmer Mac Guaranteed Securities and USDA Securities (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Jan. 01, 2014
Held-to-Maturity Securities [Abstract]
Held-to-maturity Securities, Fair Value			$ 1,600,000
Farmer Mac Guaranteed Securities and USDA Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-Sale Securities Unpaid Principal Balance	5,370,717	6,678,377
Available-for-sale Securities, Amortized Cost Basis	5,373,437	6,682,569
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	48,529	67,473
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	31,463	104,773
Available-for-sale, at fair value	5,390,503	6,645,269
Farmer Mac Guaranteed Securities [Member]
Held-to-Maturity Securities [Abstract]
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	1,794,620
Held-to-maturity Securities, Fair Value	1,800,576
Available-for-sale Securities [Abstract]
Available-for-Sale Securities Unpaid Principal Balance	3,652,904	5,087,944
Available-for-sale Securities, Amortized Cost Basis	3,652,462	5,087,551
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	36,679	64,720
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	29,860	60,671
Available-for-sale, at fair value	3,659,281	5,091,600
USDA Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-sale, at fair value	1,731,222	1,553,669
Trading Securities [Abstract]
Trading, at fair value	40,310	58,344
Available-for-sale Securities [Member] \| Farmer Mac Guaranteed Securities and USDA Securities [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	2,720	4,192
Available-for-sale Securities [Member] \| Farmer Mac Guaranteed Securities [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	(442)	(393)
Institutional Credit [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	2,400	3,200
Institutional Credit [Member] \| Farmer Mac Guaranteed Securities [Member]
Held-to-Maturity Securities [Abstract]
Held-to-Maturity Unpaid Principal Balance	1,785,340
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	1,794,620
Held to Maturity; Unrealized Holding Gains	6,211
Held to Maturity - Unrealized Holding Loss	255
Held-to-maturity Securities, Fair Value	1,800,576
Available-for-sale Securities [Abstract]
Available-for-Sale Securities Unpaid Principal Balance	3,625,073	5,066,855
Available-for-sale Securities, Amortized Cost Basis	3,625,073	5,066,980
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	36,442	64,051
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	29,853	60,665
Available-for-sale, at fair value	3,631,662	5,070,366
Institutional Credit [Member] \| Held-to-maturity Securities [Member] \| Farmer Mac Guaranteed Securities [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	9,280
Institutional Credit [Member] \| Available-for-sale Securities [Member] \| Farmer Mac Guaranteed Securities [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	0	125
USDA Guarantees [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	(200)	100
USDA Guarantees [Member] \| Farmer Mac Guaranteed Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-Sale Securities Unpaid Principal Balance	27,831	21,089
Available-for-sale Securities, Amortized Cost Basis	27,389	20,571
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	237	669
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	7	6
Available-for-sale, at fair value	27,619	21,234
USDA Guarantees [Member] \| USDA Securities [Member]
Available-for-sale Securities [Abstract]
Available-for-Sale Securities Unpaid Principal Balance	1,717,813	1,590,433
Available-for-sale Securities, Amortized Cost Basis	1,720,975	1,595,018
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	11,850	2,753
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	1,603	44,102
Available-for-sale, at fair value	1,731,222	1,553,669
Trading Securities [Abstract]
Trading Securities Unpaid Principal Balance	38,412	55,373
Trading Securities, Debt, Amortized Cost	41,160	60,345
Trading Securities, Unrealized Gains	114	193
Trading Securities, Unrealized Holding Loss	964	2,194
Trading, at fair value	40,310	58,344
USDA Guarantees [Member] \| Available-for-sale Securities [Member] \| Farmer Mac Guaranteed Securities [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	(442)	(518)
USDA Guarantees [Member] \| Available-for-sale Securities [Member] \| USDA Securities [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	3,162	4,585
USDA Guarantees [Member] \| Trading Securities [Member] \| USDA Securities [Member]
Schedule of Held-to-Maturity, Available-for-sale, and Trading Securities [Line Items]
Unamortized Premium/(Discount)	$ 2,748	$ 4,972

Available-for-Sale Securities Unpaid Principal Balance

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Held-to-Maturity Unpaid Principal Balance

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Trading Securities Unpaid Principal Balance

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Amortized cost of investments in debt securities classified as trading.

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Amount of unrealized holding gain before loss recognized in the income statement for investments in trading securities.

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