Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Nov. 15, 2021
Entity Listings [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Document Transition Report	false
Entity File Number	001-38742
Entity Registrant Name	Advent Technologies Holdings, Inc.
Entity Central Index Key	0001744494
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-0982969
Entity Address, Address Line One	200 Clarendon Street
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02116
City Area Code	617
Local Phone Number	655-6000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		51,253,591
Common Stock [Member]
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	ADN
Security Exchange Name	NASDAQ
Warrants [Member]
Entity Listings [Line Items]
Title of 12(b) Security	Warrants
Trading Symbol	ADNWW
Security Exchange Name	NASDAQ