NET INCOME (LOSS) PER COMMON SHARE - Schedule of Net Income (Loss) per Share Reconciliation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Earnings Per Share [Abstract]
Net income (loss)	$ 130,305	$ 465,174
Net income (loss) attributable to noncontrolling interests	6,081	2,282
Net income (loss) attributable to Annaly	124,224	462,892
Dividends on preferred stock	37,157	37,061
Net income (loss) available (related) to common stockholders	$ 87,067	$ 425,831
Weighted average shares of common stock outstanding-basic (in shares)	587,149,704	500,612,840
Add: Effect of stock awards, if dilutive (in shares)	1,271,294	569,203
Weighted average shares of common stock outstanding-diluted (in shares)	588,420,998	501,182,043
Net income (loss) per share available (related) to common share
Basic (in dollars per share)	$ 0.15	$ 0.85
Diluted (in dollars per share)	$ 0.15	$ 0.85