Loans and Allowance for Losses and Concentrations of Credit Risk - Financing Receivables Credit Quality Indicators (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	$ 5,310,664	[1]	$ 5,163,080	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	25,911	[1]	28,296	[2]
Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	2,832,785	[1]	2,666,857	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	6,289	[1]	8,256	[2]
Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	906,802	[1]	907,824	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	11,339	[1]	11,841	[2]
Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,256,829	[1]	1,246,105	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	5,511	[1]	4,462	[2]
Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	158,226	[1]	162,743	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	2,772	[1]	3,618	[2]
Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	147,840	[1]	170,918	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	0	[2]
Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	8,182	[1]	8,633	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	119	[2]
On-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	2,327,167	[1]	2,135,467	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	25,118	[1]	27,580	[2]
On-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,505,803	[1]	1,385,008	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	5,910	[1]	8,036	[2]
On-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	357,398	[1]	336,478	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	11,339	[1]	11,841	[2]
On-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	376,650	[1]	330,509	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	5,511	[1]	4,462	[2]
On-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	51,061	[1]	50,362	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	2,358	[1]	3,122	[2]
On-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	35,593	[1]	32,636	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	0	[2]
On-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	662	[1]	474	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	119	[2]
Off-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	2,983,497	[1]	3,027,613	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	793	[1]	716	[2]
Off-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,326,982	[1]	1,281,849	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	379	[1]	220	[2]
Off-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	549,404	[1]	571,346	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	0	[2]
Off-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	880,179	[1]	915,596	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	0	[2]
Off-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	107,165	[1]	112,381	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	414	[1]	496	[2]
Off-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	112,247	[1]	138,282	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	0	[2]
Off-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	7,520	[1]	8,159	[1]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	[1]	0	[2]
Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	146,496	[1],[3]	122,830	[1],[3]
Special Mention [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	44,218	[1],[3]	26,633	[1],[3]
Special Mention [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	18,885	[1],[3]	20,594	[1],[3]
Special Mention [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	62,651	[1],[3]	55,912	[1],[3]
Special Mention [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	2,186	[1],[3]	1,835	[1],[3]
Special Mention [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	17,991	[1],[3]	17,278	[1],[3]
Special Mention [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	565	[1],[3]	578	[1],[3]
Special Mention [Member] | On-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	65,876	[1],[3]	47,171	[1],[3]
Special Mention [Member] | On-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	30,594	[1],[3]	15,656	[1],[3]
Special Mention [Member] | On-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,620	[1],[3]	4,973	[1],[3]
Special Mention [Member] | On-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	28,429	[1],[3]	19,357	[1],[3]
Special Mention [Member] | On-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,153	[1],[3]	918	[1],[3]
Special Mention [Member] | On-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	4,080	[1],[3]	6,267	[1],[3]
Special Mention [Member] | On-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	0	[1],[3]	0	[1],[3]
Special Mention [Member] | Off-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	80,620	[1],[3]	75,659	[1],[3]
Special Mention [Member] | Off-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	13,624	[1],[3]	10,977	[1],[3]
Special Mention [Member] | Off-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	17,265	[1],[3]	15,621	[1],[3]
Special Mention [Member] | Off-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	34,222	[1],[3]	36,555	[1],[3]
Special Mention [Member] | Off-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,033	[1],[3]	917	[1],[3]
Special Mention [Member] | Off-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	13,911	[1],[3]	11,011	[1],[3]
Special Mention [Member] | Off-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	565	[1],[3]	578	[1],[3]
Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	5,012,882	[1]	4,845,302	[1]
Pass [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	2,756,848	[1]	2,600,039	[1]
Pass [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	839,312	[1]	838,318	[1]
Pass [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,159,111	[1]	1,144,438	[1]
Pass [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	140,105	[1]	144,611	[1]
Pass [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	109,990	[1]	110,059	[1]
Pass [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	7,516	[1]	7,837	[1]
Pass [Member] | On-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	2,181,158	[1]	1,988,945	[1]
Pass [Member] | On-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,457,197	[1]	1,348,205	[1]
Pass [Member] | On-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	316,996	[1]	290,064	[1]
Pass [Member] | On-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	340,433	[1]	300,308	[1]
Pass [Member] | On-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	39,591	[1]	39,022	[1]
Pass [Member] | On-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	26,279	[1]	10,987	[1]
Pass [Member] | On-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	662	[1]	359	[1]
Pass [Member] | Off-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	2,831,724	[1]	2,856,357	[1]
Pass [Member] | Off-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,299,651	[1]	1,251,834	[1]
Pass [Member] | Off-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	522,316	[1]	548,254	[1]
Pass [Member] | Off-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	818,678	[1]	844,130	[1]
Pass [Member] | Off-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	100,514	[1]	105,589	[1]
Pass [Member] | Off-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	83,711	[1]	99,072	[1]
Pass [Member] | Off-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	6,854	[1]	7,478	[1]
Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	151,286	[1],[4]	194,948	[1],[4]
Substandard [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	31,719	[1],[4]	40,185	[1],[4]
Substandard [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	48,605	[1],[4]	48,912	[1],[4]
Substandard [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	35,067	[1],[4]	45,755	[1],[4]
Substandard [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	15,935	[1],[4]	16,297	[1],[4]
Substandard [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	19,859	[1],[4]	43,581	[1],[4]
Substandard [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	101	[1],[4]	218	[1],[4]
Substandard [Member] | On-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	80,133	[1],[4]	99,351	[1],[4]
Substandard [Member] | On-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	18,012	[1],[4]	21,147	[1],[4]
Substandard [Member] | On-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	38,782	[1],[4]	41,441	[1],[4]
Substandard [Member] | On-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	7,788	[1],[4]	10,844	[1],[4]
Substandard [Member] | On-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	10,317	[1],[4]	10,422	[1],[4]
Substandard [Member] | On-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	5,234	[1],[4]	15,382	[1],[4]
Substandard [Member] | On-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	0	[1],[4]	115	[1],[4]
Substandard [Member] | Off-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	71,153	[1],[4]	95,597	[1],[4]
Substandard [Member] | Off-balance sheet [Member] | Crops [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	13,707	[1],[4]	19,038	[1],[4]
Substandard [Member] | Off-balance sheet [Member] | Permanent Plantings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	9,823	[1],[4]	7,471	[1],[4]
Substandard [Member] | Off-balance sheet [Member] | Livestock [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	27,279	[1],[4]	34,911	[1],[4]
Substandard [Member] | Off-balance sheet [Member] | Part-Time Farm [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	5,618	[1],[4]	5,875	[1],[4]
Substandard [Member] | Off-balance sheet [Member] | Agriculture Storage and Processing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	14,625	[1],[4]	28,199	[1],[4]
Substandard [Member] | Off-balance sheet [Member] | Other Commodity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	$ 101	[1],[4]	$ 103	[1],[4]

[1] Amounts represent unpaid principal balance of risk-rated loans, which is the basis Farmer Mac uses to analyze its portfolio, and recorded investment of past due loans.

[2] (1)Amounts represent unpaid principal balance of risk-rated loans, which is the basis Farmer Mac uses to analyze its portfolio, and recorded investment of past due loans.

[3] Assets in the Special mention category generally have potential weaknesses due to performance issues but are currently considered to be adequately secured.

[4] Substandard assets have a well-defined weakness or weaknesses and there is a distinct possibility that some loss will be sustained if deficiencies are not corrected.