CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net income	$ 85,224	$ 64,311
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	713	1,701
Amortization of debt premiums, discounts and issuance costs	21,744	17,078
Net change in fair value of trading securities, hedged assets, and financial derivatives	42,054	(12,232)
Losses/(gains) on sale of real estate owned	7	(784)
Total provision for losses	169	1,294
Excess Tax Benefits from Share-Based Compensation	1,105	1,170
Deferred income taxes	1,750	1,910
Other Noncash Income (Expense)	0	(11)
Stock-based compensation expense	1,882	2,597
Proceeds from repayment of loans purchased as held for sale	76,259	54,919
Net change in:
Interest receivable	18,537	12,678
Guarantee and commitment fees receivable	(86)	226
Other assets	(7,268)	(109)
Accrued interest payable	12,033	12,104
Other liabilities	(1,898)	435
Net cash provided by operating activities	252,225	157,309
Cash flows from investing activities:
Purchases of loans held for investment	(684,486)	(1,047,001)
Purchases of defaulted loans	(7,756)	(3,458)
Proceeds from repayment of loans purchased as held for investment	508,969	368,826
Proceeds from sale of Farmer Mac Guaranteed Securities	305,391	404,246
Proceeds from sale of real estate owned	116	6,464
Net cash used by investing activities	(239,793)	(1,777,246)
Cash flows from financing activities:
Payments to third parties on debt securities of consolidated trusts	(117,966)	(86,582)
Proceeds from common stock issuance	7	235
Tax payments related to share-based awards	(2,635)	(2,283)
Dividends paid on common and preferred stock	(28,421)	(21,321)
Net cash provided by financing activities	121,698	1,721,472
Net increase in cash and cash equivalents	134,130	101,535
Cash and cash equivalents at beginning of period	302,022	265,229
Cash and cash equivalents at end of period	436,152	366,764
Medium-term Notes [Member]
Cash flows from financing activities:
Proceeds from issuance of discount notes and medium-term notes	6,109,613	7,160,298
Payments to redeem discount notes and medium-term notes	(5,254,430)	(3,416,300)
Notes Payable to Banks [Member]
Cash flows from financing activities:
Proceeds from issuance of discount notes and medium-term notes	30,946,426	40,262,122
Payments to redeem discount notes and medium-term notes	(31,530,896)	(42,174,697)
Investment Securities [Member]
Cash flows from investing activities:
Purchases of available-for-sale investment securities and Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	(833,650)	(614,423)
Proceeds from repayment of available-for-sale investment securities, Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	814,712	895,497
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	(2,544,812)	(2,580,229)
Proceeds from repayment of available-for-sale investment securities, Farmer Mac Guaranteed Securities and USDA Guaranteed Securities	$ 2,201,723	$ 787,743