Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Mar. 13, 2022	Jun. 30, 2021
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Entity File Number	1-13412
Entity Registrant Name	HUDSON TECHNOLOGIES INC /NY
Entity Incorporation, State or Country Code	NY
Entity Tax Identification Number	13-3641539
Entity Address, Address Line One	300 Tice Boulevard
Entity Address, Address Line Two	Suite 290
Entity Address, City or Town	Woodcliff Lake
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07677
City Area Code	845
Local Phone Number	735-6000
Title of 12(b) Security	Common stock, $0.01 par value
Security Exchange Name	NASDAQ
Trading Symbol	HDSN
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		44,810,415
Entity Central Index Key	0000925528
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Public Float			$ 141,917,622
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Auditor Name	BDO USA, LLP
Auditor Firm ID	243
Auditor Location	Stamford
ICFR Auditor Attestation Flag	true