Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 30, 2020
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Entity Registrant Name	ANI PHARMACEUTICALS INC
Entity Current Reporting Status	Yes
Entity Central Index Key	0001023024
Current Fiscal Year End Date	--12-31
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Trading Symbol	ANIP
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		12,329,884
Class C Special Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		10,864