Off-Balance Sheet Guarantees and Long Term Standby Purchase Commitments - Off-Balance Sheet Guaranteed Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2014 Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Off Balance Sheet Farmer Mac Guaranteed Securities [Member]	Dec. 31, 2013 Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Off Balance Sheet Farmer Mac Guaranteed Securities [Member]	Mar. 31, 2014 Farm & Ranch [Member] Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Off Balance Sheet Farm & Ranch Guaranteed Securities [Member]	Dec. 31, 2013 Farm & Ranch [Member] Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Off Balance Sheet Farm & Ranch Guaranteed Securities [Member]	Mar. 31, 2014 Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member]	Dec. 31, 2013 Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member]	Mar. 31, 2014 Institutional Credit [Member] [Member] Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Farmer Mac Guaranteed Securities AgVantage [Member]	Dec. 31, 2013 Institutional Credit [Member] [Member] Off-balance sheet [Member] Variable Interest Entity, Not Primary Beneficiary [Member] Farmer Mac Guaranteed Securities AgVantage [Member]
Long-term Purchase Commitment [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 1,739,335	$ 1,766,982	$ 731,574	$ 765,751	$ 19,562	$ 20,222	$ 988,199	$ 981,009
Loans and leases receivable, impaired, loans past due period, minimum	90 days