CONSOLIDATED STATEMENTS OF EQUITY Statement - USD ($) $ in Thousands	Total	Common Class C, Non-Voting [Member]	Preferred Stock [Member]	Preferred Stock [Member] Common Class C, Non-Voting [Member]	Common Stock [Member]	Common Stock [Member] Common Class C, Non-Voting [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Common Class C, Non-Voting [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Other Comprehensive Income (Loss) [Member] Common Class C, Non-Voting [Member]	Retained Earnings [Member]	Retained Earnings [Member] Common Class C, Non-Voting [Member]	Noncontrolling Interest [Member]	Noncontrolling Interest [Member] Common Class C, Non-Voting [Member]
Beginning Balance (Shares Outstanding) at Dec. 31, 2015			8,400,000		10,687,000
Beginning Balance at Dec. 31, 2015	$ 553,720		$ 204,759		$ 10,687		$ 117,862		$ (11,019)		$ 231,228		$ 203
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Attributable to Farmer Mac	13,612		0		0		0		0		13,612		0
Less: Net loss attributable to non-controlling interest	28		0		0		0		0		0		(28)
Other comprehensive income, net of tax	(7,898)		0		0		0		(7,898)		0		0
Preferred stock	(3,295)		0		0		0		0		(3,295)		0
Common stock	(2,702)		0		0		0		0		(2,702)		0
Stock Issued During Period, Shares, New Issues				0		71,000
Stock Issued During Period, Value, New Issues		$ 169		$ 0		$ 71		$ 98		$ 0		$ 0		$ 0
Repurchase of Class C Common Stock				0		(307,000)
Repurchase of Class C Common Stock		(9,088)		$ 0		$ (307)		0		0		(8,781)		0
Stock-based compensation cost	1,027		0		0		1,027		0		0		0
Other stock-based award activity	(1,553)		0		0		(1,553)		0		0		0
Investment in subsidiary - non-controlling interest	52		$ 0		$ 0		0		0		0		52
Ending Balance (Shares Outstanding) at Mar. 31, 2016			8,400,000		10,451,000
Ending Balance at Mar. 31, 2016	544,016		$ 204,759		$ 10,451		117,434		(18,917)		230,062		227
Beginning Balance (Shares Outstanding) at Dec. 31, 2016			8,400,000		10,539,000
Beginning Balance at Dec. 31, 2016	643,647		$ 204,759		$ 10,539		118,655		33,758		275,714		222
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Attributable to Farmer Mac	21,910		0		0		0		0		21,910
Less: Net loss attributable to non-controlling interest	15		0		0		0		0		0		(15)
Other comprehensive income, net of tax	7,786		0		0		0		7,786		0		0
Preferred stock	(3,295)		0		0		0		0		(3,295)		0
Common stock	(3,799)		0		0		0		0		(3,799)		0
Stock Issued During Period, Shares, New Issues				0		57,000
Stock Issued During Period, Value, New Issues		$ 201		$ 0		$ 57		$ 144		$ 0		$ 0		$ 0
Repurchase of Class C Common Stock		(668,000)
Stock-based compensation cost	981		0		0		981		0		0		0
Other stock-based award activity	(1,394)		0		0		(1,394)		0		0		0
Investment in subsidiary - non-controlling interest	0		$ 0		$ 0		0		0		0		0
Ending Balance (Shares Outstanding) at Mar. 31, 2017			8,400,000		10,596,000
Ending Balance at Mar. 31, 2017	$ 666,022		$ 204,759		$ 10,596		$ 118,386		$ 41,544		$ 290,530		$ 207