Commitments and Contingencies - Summary of Material Contractual Obligations and Commercial Commitments (Details) $ in Millions	Dec. 31, 2018 USD ($)
Commitment And Contingencies [Line Items]
Property leases, Total	$ 193
Property leases, Less than 1 year	25
Property leases, 1 to 3 years	49
Property leases, 3 to 5 years	43
Property leases, More than 5 years	76
Contractual Obligation, Total	218
Contractual Obligation, Less than 1 year	34
Contractual Obligation, 1 to 3 years	60
Contractual Obligation, 3 to 5 years	47
Contractual Obligation, More than 5 years	77
Standby Letters of Credit
Commitment And Contingencies [Line Items]
Letters of credit outstanding amount	3
Expected Commitment Fee Payments on 2015 Credit Facility
Commitment And Contingencies [Line Items]
Contractual Obligation, Total	6
Contractual Obligation, Less than 1 year	2
Contractual Obligation, 1 to 3 years	3
Contractual Obligation, 3 to 5 years	1
Purchase Obligations and Other
Commitment And Contingencies [Line Items]
Contractual Obligation, Total	19
Contractual Obligation, Less than 1 year	7
Contractual Obligation, 1 to 3 years	8
Contractual Obligation, 3 to 5 years	3
Contractual Obligation, More than 5 years	$ 1

Commitment and contingencies.

No definition available.

Name:	trip_CommitmentAndContingenciesLineItems
Namespace Prefix:	trip_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligationDueAfterFifthYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due in the fourth and fifth fiscal years following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligationDueInFourthAndFifthYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligationDueInNextTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation due in the second and third fiscal years following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligationDueInSecondAndThirdYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

+ Details

Name:	us-gaap_OperatingLeasesFutureMinimumPaymentsDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

+ Details

Name:	us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth and fifth fiscal years following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourAndFiveYears
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second and third fiscal years following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoAndThreeYears
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_StandbyLettersOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=trip_ExpectedCommitmentFeePaymentsOnTwoThousandFifteenCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=trip_PurchaseObligationsAndOtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: