CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net income	$ 55,455	$ 42,529
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	1,536	534
Amortization of debt premiums, discounts and issuance costs	13,701	11,479
Net change in fair value of trading securities, hedged assets, and financial derivatives	26,100	(12,122)
(Gains)/losses on sale of real estate owned	(34)	(752)
Total provision for losses	172	910
Excess Tax Benefits from Share-Based Compensation	903	832
Deferred income taxes	(2,457)	2,095
Other Noncash Income (Expense)	0	(100)
Stock-based compensation expense	1,269	1,784
Proceeds from repayment of loans purchased as held for sale	62,078	32,510
Net change in:
Interest receivable	(879)	(3,700)
Guarantee and commitment fees receivable	8	320
Other assets	(12,877)	300
Accrued interest payable	13,104	14,260
Other liabilities	4,075	(488)
Net cash provided by operating activities	162,154	90,591
Cash flows from investing activities:
Purchases of loans held for investment	(491,858)	(678,710)
Purchases of defaulted loans	(721)	(415)
Proceeds from repayment of loans purchased as held for investment	335,808	250,111
Proceeds from sale of Farmer Mac Guaranteed Securities	196,290	247,975
Proceeds from sale of real estate owned	101	6,144
Net cash used by investing activities	(609,078)	(1,428,004)
Cash flows from financing activities:
Payments to third parties on debt securities of consolidated trusts	(72,031)	(54,949)
Proceeds from common stock issuance	7	232
Tax payments related to share-based awards	(2,523)	(1,669)
Dividends paid on common and preferred stock	(18,939)	(14,207)
Net cash provided/(used) by financing activities	575,714	1,392,177
Net increase in cash and cash equivalents	128,790	54,764
Cash and cash equivalents at beginning of period	302,022	265,229
Cash and cash equivalents at end of period	430,812	319,993
Medium-term Notes [Member]
Cash flows from financing activities:
Proceeds from issuance of discount notes and medium-term notes	4,103,234	5,257,762
Payments to redeem discount notes and medium-term notes	(3,313,236)	(2,206,300)
Notes Payable to Banks [Member]
Cash flows from financing activities:
Proceeds from issuance of discount notes and medium-term notes	21,036,787	27,501,915
Payments to redeem discount notes and medium-term notes	(21,157,585)	(29,090,607)
Investment Securities [Member]
Cash flows from investing activities:
Purchases of available-for-sale investment securities and Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	(539,667)	(271,684)
Proceeds from repayment of available-for-sale investment securities, Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	403,018	508,409
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	(1,843,294)	(2,108,174)
Proceeds from repayment of available-for-sale investment securities, Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	$ 1,331,245	$ 618,340