Statements of Operations (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Research and development expense to related party	$ 0	$ 0	$ 2,359

Research and development expense to related party.

No definition available.

Name:	pcvx_ResearchAndDevelopmentExpenseToRelatedParty
Namespace Prefix:	pcvx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration