Document And Entity Information - shares	1 Months Ended
	Sep. 30, 2020	Dec. 14, 2020
Document Information Line Items
Entity Registrant Name	Duddell Street Acquisition Corp.
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Central Index Key	0001823466
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Shell Company	true
Entity Ex Transition Period	false
Document Transition Report	false
Entity File Number	333-249207
Entity Incorporation, State or Country Code	E9
Entity Interactive Data Current	Yes
Class A Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		17,500,000
Class B Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		4,375,000