Farmer Mac Guaranteed Securities and USDA Securities - Farmer Mac Guaranteed Securities and USDA Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Held-to-maturity:
Allowance for losses	$ (546)
Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unpaid Principal Balance	3,448,941	$ 3,638,142
Amortized Cost	3,481,187	3,679,611
Unrealized Gains	116,945	70,495
Unrealized Losses	(661)	(922)
Fair Value	3,596,925
Fair Value	3,596,925	3,749,184
Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	1,141,257	1,447,471
Amortized Cost	1,141,264	1,447,451
Allowance for losses	(546)
Unrealized Gains	31,319	16,139
Unrealized Losses	0	(164)
Fair Value	1,172,037
Fair Value		1,463,426
Available-for-sale:
Amortized Cost	7,539,944
Fair Value	7,898,387
USDA Securities:
Trading:
Fair Value	7,786	8,913
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities and USDA Securities
Held-to-maturity:
Unamortized Premium/(Discount)	32,246	41,469
Available-for-sale:
Unamortized Premium/(Discount)	32,246	41,469
Trading:
Unamortized Premium/(Discount)	32,246	41,469
Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	7	(20)
Available-for-sale:
Unamortized Premium/(Discount)	7	(20)
Trading:
Unamortized Premium/(Discount)	7	(20)
Institutional Credit
Trading:
Available-for-sale, accrued interest excluded	34,900
Held-to-maturity, accrued interest excluded	35,300
Trading securities, accrued interest excluded	200
Institutional Credit \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	1,108,720	1,415,584
Amortized Cost	1,108,650	1,415,410
Allowance for losses	(546)
Unrealized Gains	30,070	15,300
Unrealized Losses	0	(164)
Fair Value	1,138,174
Fair Value		1,430,546
Available-for-sale:
Unpaid Principal Balance	7,540,043	7,017,095
Amortized Cost	7,539,944	7,016,971
Allowance for losses	(235)
Unrealized Gains	405,926	161,316
Unrealized Losses	(47,248)	(35,262)
Fair Value	7,898,387	7,143,025
Institutional Credit \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(70)	(174)
Available-for-sale:
Unamortized Premium/(Discount)	(70)	(174)
Trading:
Unamortized Premium/(Discount)	(70)	(174)
Institutional Credit \| Available-for-Sale Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	(99)	(124)
Available-for-sale:
Unamortized Premium/(Discount)	(99)	(124)
Trading:
Unamortized Premium/(Discount)	(99)	(124)
USDA Guarantees
Held-to-maturity:
Unamortized Premium/(Discount)	(100)	200
Available-for-sale:
Unamortized Premium/(Discount)	(100)	200
Trading:
Unamortized Premium/(Discount)	(100)	200
USDA Guarantees \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unpaid Principal Balance	32,537	31,887
Amortized Cost	32,614	32,041
Allowance for losses	0
Unrealized Gains	1,249	839
Unrealized Losses	0	0
Fair Value	33,863
Fair Value		32,880
USDA Guarantees \| USDA Securities:
Held-to-maturity:
Unpaid Principal Balance	2,307,684	2,190,671
Amortized Cost	2,339,923	2,232,160
Allowance for losses	0
Unrealized Gains	85,626	54,356
Unrealized Losses	(661)	(758)
Fair Value	2,424,888
Fair Value		2,285,758
Trading:
Unpaid Principal Balance	7,276	8,400
Amortized Cost	7,667	8,879
Allowance for losses	0
Unrealized Gains	122	61
Unrealized Losses	(3)	(27)
Fair Value	$ 7,786	$ 8,913
Trading securities, weighted-average yield	5.15%	5.20%
USDA Guarantees \| Held-to-Maturity Securities \| Farmer Mac Guaranteed Securities
Held-to-maturity:
Unamortized Premium/(Discount)	$ 77	$ 154
Available-for-sale:
Unamortized Premium/(Discount)	77	154
Trading:
Unamortized Premium/(Discount)	77	154
USDA Guarantees \| Held-to-Maturity Securities \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	32,239	41,489
Available-for-sale:
Unamortized Premium/(Discount)	32,239	41,489
Trading:
Unamortized Premium/(Discount)	32,239	41,489
USDA Guarantees \| Trading Securities \| USDA Securities:
Held-to-maturity:
Unamortized Premium/(Discount)	391	479
Available-for-sale:
Unamortized Premium/(Discount)	391	479
Trading:
Unamortized Premium/(Discount)	$ 391	$ 479

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