Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Aug. 15, 2023
Document Information Line Items
Entity Registrant Name	CONSTELLATION ACQUISITION CORP I
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Central Index Key	0001834032
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Jun. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Shell Company	true
Entity Ex Transition Period	false
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	E9
Entity File Number	001-39945
Entity Tax Identification Number	98-1574835
Entity Address, Address Line One	200 Park Ave
Entity Address, Address Line Two	32nd Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
City Area Code	(914)
Local Phone Number	615-9912
Entity Interactive Data Current	Yes
Entity Address, Postal Zip Code	00000
Class A ordinary shares, par value $0.0001 per share
Document Information Line Items
Trading Symbol	CSTA
Title of 12(b) Security	Class A ordinary shares, par value $0.0001 per share
Security Exchange Name	NYSE
Redeemable warrants, each one whole warrant exercisable for one share of Class A ordinary shares at an exercise price of $11.50
Document Information Line Items
Trading Symbol	CSTA.WS
Title of 12(b) Security	Redeemable warrants, each one whole warrant exercisable for one share of Class A ordinary shares at an exercise price of $11.50
Security Exchange Name	NYSE
Units, each consisting of one share of Class A ordinary shares and one-third of one redeemable warrant [Member]
Document Information Line Items
Trading Symbol	CSTA.U
Title of 12(b) Security	Units, each consisting of one share of Class A ordinary shares and one-third of one redeemable warrant
Security Exchange Name	NYSE
Class A Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		4,493,843
Class B Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		7,750,000