S-K 1602(b)(6) Prospectus Summary, Sponsor Compensation - Collective Acquisition Sponsor II LLC [Member]	Mar. 27, 2026 USD ($) $ / shares shares
SPAC Prospectus Summary, Sponsor Compensation [Line Items]
Price Paid or to be Paid for Securities, Total Amount	$ 300,000
Administrative Services Fee [Member]
SPAC Prospectus Summary, Sponsor Compensation [Line Items]
Price Paid or to be Paid for Securities, Total Amount	25,000
Class B Ordinary Shares [Member]
SPAC Prospectus Summary, Sponsor Compensation [Line Items]
Price Paid or to be Paid for Securities, Total Amount	$ 25,000
Securities Issued or to be Issued, Shares (in Shares) \| shares	8,433,333
Private Warrants [Member]
SPAC Prospectus Summary, Sponsor Compensation [Line Items]
Price Paid or to be Paid for Securities, Total Amount	$ 4,670,000
Securities Issued or to be Issued, Shares (in Shares) \| shares	4,670,000
Price Paid or to be Paid for Securities, Per Share (in Dollars per share) \| $ / shares	$ 1
Over-Allotment Option [Member]
SPAC Prospectus Summary, Sponsor Compensation [Line Items]
Price Paid or to be Paid for Securities, Total Amount	$ 5,000,000
Securities Issued or to be Issued, Shares (in Shares) \| shares	5,000,000
Working Capital Loans [Member]
SPAC Prospectus Summary, Sponsor Compensation [Line Items]
Price Paid or to be Paid for Securities, Total Amount	$ 1,500,000