Nature of Business and Basis of Presentation - Additional Information (Details) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 16, 2021	Sep. 30, 2021 USD ($) ClinicalTrial	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) ft² ClinicalTrial	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Description Of Organization And Business Operations Details [Line Items]
Date of incorporation				Aug. 24, 2018
Business combination, shares exchange ratio description	1.00 share of Legacy Celularity for approximately 0.7686 shares of Celularity
Business combination, shares exchange ratio	0.7686
Number of clinical trials | ClinicalTrial		4		4
Area of building | ft²				150,000
Substantial doubt about going concern, within one year [true false]				true
Net loss		$ 49,938	$ (46,325)	$ (96,078)	$ (212,143)	$ (208,233)
Accumulated deficit		$ (659,641)		$ (659,641)		$ (563,563)
Legacy Celularity
Description Of Organization And Business Operations Details [Line Items]
Business combination, shares exchange ratio	1.00