Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2017	Aug. 25, 2017	Dec. 31, 2016
Document Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2017
Trading Symbol	CTLT
Document Fiscal Period Focus	FY
Entity Registrant Name	Catalent, Inc.
Entity Central Index Key	0001596783
Current Fiscal Year End Date	--06-30
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Public Float			$ 3,400.0
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding (shares)		125,175,734