Subsequent Events (Details) (USD $)	0 Months Ended	12 Months Ended
	Mar. 30, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Farmer Mac II LLC [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Preferred Stock, Shares Outstanding	250,000
Preferred Stock, Dividends Per Share, Declared	$ 22.1875
Preferred Stock, Redemption Date	Mar. 30, 2015
Preferred Stock, Redemption Price Per Share	$ 1,000
Preferred Stock, Redemption Amount	$ 250,000,000
Non-controlling Interest - Preferred Stock [Member]
Subsequent Event [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests		$ 6,000,000	$ 0	$ 0