CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	7.875% Series A Cumulative Redeemable Preferred Stock	7.625% Series C Cumulative Redeemable Preferred Stock	7.50% Series D Cumulative Redeemable Preferred Stock	7.625% Series E Cumulative Redeemable Preferred Stock	6.95% Series F Cumulative Redeemable Preferred Stock	6.50% Series G Cumulative Redeemable Preferred Stock	Preferred Stock	Common Stock	Additional paid-in capital	Accumulated other comprehensive income (loss)	Accumulated deficit	Total stockholder’s equity	Noncontrolling interests
Beginning balance at Dec. 31, 2016								$ 1,200,559	$ 10,189	$ 15,579,342	$ (1,085,893)	$ (3,136,017)		$ 7,792
Stock compensation expense										1,276
Issuance								696,910	690	803,464
Acquisition of subsidiary								0	0	0
Redemption of preferred stock								(177,088)		(8,224)
Direct purchase and dividend reinvestment	$ 1,949								2	1,947
Unrealized gains (losses) on available-for-sale securities	397,600										397,600
Reclassification adjustment for net (gains) losses included in net income (loss)	48,144										48,144
Net income (loss) attributable to Annaly	822,682											822,682
Dividends declared on preferred stock		$ (9,527)	$ (17,157)	$ (25,875)	$ (16,441)	$ 0	$ 0					(69,000)
Dividends and dividend equivalents declared on common stock and share-based awards	(937,825)											(937,825)
Net income (loss) attributable to noncontrolling interests	437													(437)
Equity contributions from (distributions to) noncontrolling interest														(895)
Ending balance at Sep. 30, 2017	14,155,218							1,720,381	10,881	16,377,805	(640,149)	(3,320,160)	$ 14,148,758	6,460
Beginning balance at Dec. 31, 2017	14,871,573							1,720,381	11,596	17,221,265	(1,126,020)	(2,961,749)		6,100
Stock compensation expense										1,789
Issuance								411,335	1,103	1,116,409
Acquisition of subsidiary								55,000	330	455,613
Redemption of preferred stock			(125,000)		(287,500)			(408,548)		(3,952)
Direct purchase and dividend reinvestment	2,584								2	2,582
Unrealized gains (losses) on available-for-sale securities	(3,104,218)										(3,104,218)
Reclassification adjustment for net (gains) losses included in net income (loss)	407,282										407,282
Net income (loss) attributable to Annaly	2,309,297											2,309,297
Dividends declared on preferred stock		$ 0	$ (10,987)	$ (25,875)	$ (2,253)	$ (37,530)	$ (19,875)					(96,818)
Dividends and dividend equivalents declared on common stock and share-based awards	(1,062,685)											(1,062,685)
Net income (loss) attributable to noncontrolling interests	277													(277)
Equity contributions from (distributions to) noncontrolling interest														39
Ending balance at Sep. 30, 2018	$ 14,955,856							$ 1,778,168	$ 13,031	$ 18,793,706	$ (3,822,956)	$ (1,811,955)	$ 14,949,994	$ 5,862