CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net income	$ 42,529	$ 28,870
Adjustments to reconcile net income to net cash provided by operating activities:
Net amortization of deferred gains, premiums, and discounts on loans, investments, Farmer Mac Guaranteed Securities, and USDA Securities	534	1,035
Amortization of debt premiums, discounts and issuance costs	11,479	16,143
Net change in fair value of trading securities, hedged assets, and financial derivatives	(12,122)	4,314
Gains on sale of real estate owned	(752)	0
Total provision for losses	910	521
Excess Tax Benefits from Share-Based Compensation	832	0
Deferred income taxes	2,095	(1,964)
Other Noncash Income (Expense)	100	9
Stock-based compensation expense	1,784	1,788
Proceeds from repayment of trading investment securities	0	325
Proceeds from repayment of loans purchased as held for sale	32,510	37,460
Net change in:
Interest receivable	(3,700)	6,300
Guarantee and commitment fees receivable	320	536
Other assets	300	(54,970)
Accrued interest payable	14,260	285
Other liabilities	(488)	(1,777)
Net cash provided by operating activities	90,591	38,875
Cash flows from investing activities:
Purchases of loans held for investment	(678,710)	(459,315)
Purchases of defaulted loans	(415)	(1,415)
Proceeds from repayment of loans purchased as held for investment	250,111	199,357
Proceeds from sale of Farmer Mac Guaranteed Securities	247,975	278,443
Proceeds from sale of real estate owned	6,144	0
Net cash used by investing activities	(1,428,004)	(173,829)
Cash flows from financing activities:
Excess tax benefits related to stock-based awards	0	253
Payments to third parties on debt securities of consolidated trusts	(54,949)	(41,259)
Proceeds from common stock issuance	232	137
Tax payments related to share-based awards	(1,669)	(1,722)
Investment in subsidiary - non-controlling interest	0	53
Dividends paid on common and preferred stock	(14,207)	(12,012)
Net cash provided by financing activities	1,392,177	689,496
Net increase in cash and cash equivalents	54,764	554,542
Cash and cash equivalents at beginning of period	265,229	1,210,084
Cash and cash equivalents at end of period	319,993	1,764,626
Medium-term Notes [Member]
Cash flows from financing activities:
Proceeds from issuance of discount notes and medium-term notes	5,257,762	2,843,542
Payments to redeem discount notes and medium-term notes	(2,206,300)	(2,040,800)
Discount Notes [Member]
Cash flows from financing activities:
Proceeds from issuance of discount notes and medium-term notes	27,501,915	48,914,061
Payments to redeem discount notes and medium-term notes	(29,090,607)	(48,963,471)
Investment Securities [Member]
Cash flows from investing activities:
Purchases of available-for-sale investment securities and Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	(271,684)	(341,099)
Proceeds from repayment of available-for-sale investment securities, Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	508,409	624,402
Proceeds from sale of available-for-sale investment securities	0	186,769
Farmer Mac Guaranteed Securities and USDA Securities [Member]
Cash flows from investing activities:
Purchases of available-for-sale investment securities and Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	(2,108,174)	(1,506,177)
Proceeds from repayment of available-for-sale investment securities, Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	618,340	845,206
Common Class C, Non-Voting [Member]
Cash flows from financing activities:
Common stock repurchased	$ 0	$ (9,286)