Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2026	May 15, 2026
Document Information Line Items
Entity Central Index Key	0002076739
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Fiscal Year Focus	2026
Document Transition Report	false
Entity File Number	001-42977
Entity Registrant Name	SC II Acquisition Corp.
Entity Incorporation, State or Country Code	E9
Entity Tax Identification Number	98-1876716
Entity Address, Address Line One	575 Fifth Avenue
Entity Address, Address Line Two	14th Floor
Entity Address, State or Province	NY
Entity Address, City or Town	New York
Entity Address, Postal Zip Code	10017
City Area Code	(646)
Local Phone Number	257-4214
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	true
Amendment Flag	false
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Units, each consisting of one Class A Ordinary Share and one Right
Document Information Line Items
Title of 12(b) Security	Units, each consisting of one Class A Ordinary Share and one Right
Trading Symbol	SCIIU
Security Exchange Name	NASDAQ
Class A Ordinary Shares, par value $0.0001 per share
Document Information Line Items
Title of 12(b) Security	Class A Ordinary Shares, par value $0.0001 per share
Trading Symbol	SCII
Security Exchange Name	NASDAQ
Rights, each Right entitling the holder to receive one-fifth (1/5) of one Class A Ordinary Share
Document Information Line Items
Title of 12(b) Security	Rights, each Right entitling the holder to receive one-fifth (1/5) of one Class A Ordinary Share
Trading Symbol	SCIIR
Security Exchange Name	NASDAQ
Class A Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		17,505,000
Class B Ordinary Shares
Document Information Line Items
Entity Common Stock, Shares Outstanding		7,392,857