Goodwill - Rollforward (Detail) $ in Millions	6 Months Ended
Dec. 31, 2016 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 996.5
Additions/(impairments)	48.7
Foreign currency translation adjustments	(36.7)
Ending balance	1,008.5
Softgel Technologies [Member]
Goodwill [Roll Forward]
Beginning balance	405.9
Additions/(impairments)	0.0
Foreign currency translation adjustments	(12.9)
Ending balance	393.0
Drug Delivery Solutions [Member]
Goodwill [Roll Forward]
Beginning balance	435.1
Additions/(impairments)	48.7
Foreign currency translation adjustments	(13.8)
Ending balance	470.0
Clinical Supply Services [Member]
Goodwill [Roll Forward]
Beginning balance	155.5
Additions/(impairments)	0.0
Foreign currency translation adjustments	(10.0)
Ending balance	$ 145.5

Goodwill, Acquired During Period (Impairment Loss)

No definition available.

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Namespace Prefix:	ctlt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

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- Details

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- Details

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- Details

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