Farmer Mac Guaranteed Securities and USDA Guaranteed Securities - Trading Securities (Details) - USDA Securities [Member] - USD ($) $ in Thousands |
Dec. 31, 2015 |
Dec. 31, 2014 |
|---|---|---|
| Schedule of Trading Securities and Other Trading Assets [Line Items] | ||
| Trading, at fair value | $ 28,975 | $ 40,310 |
| USDA Guarantees [Member] | ||
| Schedule of Trading Securities and Other Trading Assets [Line Items] | ||
| Trading Securities, Debt, Amortized Cost | 29,063 | 41,160 |
| Trading, at fair value | $ 28,975 | $ 40,310 |
| Trading Securities, Weighted-Average Yield | 5.53% | 5.60% |