Noncontrolling Interest, Number Of Shares Owned By Parent

No definition available.

Name:	elan_NoncontrollingInterestNumberOfSharesOwnedByParent
Namespace Prefix:	elan_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

+ Details

Name:	us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsidiarySaleOfStockLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1448-109256

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

+ Details

Name:	us-gaap_WeightedAverageNumberOfSharesOutstandingBasic
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_IPOMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=elan_ElancoAnimalHealthIncorporatedAndSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=elan_EliLillyandCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Retirement Benefits - Change in Benefit Obligation, Change in Plan Assets, and Funded Status (Details)			3 Months Ended		12 Months Ended
	Sep. 24, 2018 shares	Sep. 19, 2018	Mar. 31, 2019 shares	Mar. 31, 2018 shares	Dec. 31, 2016 shares	Sep. 18, 2018 shares	Dec. 31, 2017 shares
Subsidiary, Sale of Stock [Line Items]
Stock split ratio		2,932,900
Number of shares outstanding			365,700,000	293,300,000	293,290,000
IPO
Subsidiary, Sale of Stock [Line Items]
Number of shares issued	72,335,000
Elanco \| Lilly
Subsidiary, Sale of Stock [Line Items]
Common shares outstanding						100	293,290,000