Number of common stock shares held by related party.

No definition available.

Name:	trip_CommonStockSharesHeldByRelatedParty
Namespace Prefix:	trip_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of common stock owned by a related party.

+ References

No definition available.

+ Details

Name:	trip_PercentOfCommonStockHeldByRelatedPartyCurrent
Namespace Prefix:	trip_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of common stock owned by a related party if Class B shares were converted to common shares.

+ References

No definition available.

+ Details

Name:	trip_PercentOfCommonStockHeldByRelatedPartyIfClassBConverted
Namespace Prefix:	trip_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The voting rights percentage assuming the related party voted both common and class B stock.

+ References

No definition available.

+ Details

Name:	trip_RelatedPartyVotingRightsPercentCurrent
Namespace Prefix:	trip_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

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

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

+ Details

Name:	us-gaap_RelatedPartyTransactionAmountsOfTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=trip_LTRIPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Related Party Transactions - Additional Information (Details) - LTRIP - USD ($) shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Related Party Transaction [Line Items]
Beneficially ownership of shares of common stock			18.2
Percentage taken from outstanding shares of common stock			14.30%
Percentage of beneficially ownership of shares of common stock class B			22.20%
Right to voting			one vote per share
Beneficially ownership of equity securities			57.40%
Related party transactions	$ 0	$ 0	$ 0	$ 0
Class B Common Stock
Related Party Transaction [Line Items]
Beneficially ownership of shares of common stock			12.8
Percentage taken from outstanding shares of common stock			100.00%
Right to voting			ten votes per share