The senior notes were issued at a percentage of par (less than 100% of par results in a discount).

No definition available.

Name:	expe_SeniorNotesIssuedPricePercentage
Namespace Prefix:	expe_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_InterestPayableCurrentAndNoncurrent
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

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=expe_SevenPointFourFiveSixPercentSeniorNotesDueOnTwoZeroOneEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=expe_FivePointNineFivePercentSeniorNotesDueOnTwoZeroTwoZeroMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=expe_TwoPointFivePercentSeniorNotesDueOnTwoZeroTwoTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=expe_FourPointFivePercentSeniorNotesDueOnTwoZeroTwoFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=expe_FivePointZeroPercentSeniorNotesDueOnTwoZeroTwoSixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=expe_ThreePointEightPercentSeniorNotesDueOnTwoZeroTwoEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt - Additional Information (Detail)	12 Months Ended
Debt - Additional Information (Detail)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 EUR (€)	Aug. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 EUR (€)	Sep. 30, 2016	Jun. 30, 2015 EUR (€)
Senior Notes
Debt Instrument [Line Items]
Accrued interest related to senior notes	$ 65,000,000			$ 75,000,000
Credit Facility
Debt Instrument [Line Items]
Credit facility	$ 2,000,000,000			1,500,000,000
Commitment fee on undrawn amounts	0.175%
Basis points added to LIBOR rate	1.25%
Letters of credit issued under the credit facility	$ 15,000,000			$ 14,000,000
Uncommitted Credit Facility \| International Subsidiary One
Debt Instrument [Line Items]
Credit facility \| €		€ 50,000,000
Credit facility borrowings outstanding \| €		€ 0			€ 0
7.456% Senior Notes Due 2018
Debt Instrument [Line Items]
Senior unsecured notes principal amount			$ 500,000,000
Senior notes, interest rate	7.456%	7.456%	7.456%	7.456%	7.456%
5.95% Senior Notes Due 2020
Debt Instrument [Line Items]
Senior unsecured notes principal amount	$ 750,000,000
Senior notes, interest rate	5.95%	5.95%		5.95%	5.95%	5.95%
Debt instrument redemption price percentage	100.00%
Senior notes issued price percentage	99.893%	99.893%
5.95% Senior Notes Due 2020 \| Upon the occurrence of certain change of control triggering events
Debt Instrument [Line Items]
Debt instrument redemption price percentage	101.00%
2.5% Senior Notes Due 2022
Debt Instrument [Line Items]
Senior unsecured notes principal amount \| €		€ 650,000,000			€ 650,000,000		€ 650,000,000
Senior notes, interest rate	2.50%	2.50%		2.50%	2.50%	2.50%	2.50%
Debt instrument redemption price percentage	100.00%
Senior notes issued price percentage	99.525%	99.525%
2.5% Senior Notes Due 2022 \| Upon the occurrence of certain change of control triggering events
Debt Instrument [Line Items]
Debt instrument redemption price percentage	101.00%
4.5% Senior Notes Due 2024
Debt Instrument [Line Items]
Senior unsecured notes principal amount	$ 500,000,000
Senior notes, interest rate	4.50%	4.50%		4.50%	4.50%	4.50%
Debt instrument redemption price percentage	100.00%
Senior notes issued price percentage	99.444%	99.444%
4.5% Senior Notes Due 2024 \| Upon the occurrence of certain change of control triggering events
Debt Instrument [Line Items]
Debt instrument redemption price percentage	101.00%
5.0% Senior Notes Due 2026
Debt Instrument [Line Items]
Senior unsecured notes principal amount	$ 750,000,000
Senior notes, interest rate	5.00%	5.00%		5.00%	5.00%	5.00%
Debt instrument redemption price percentage	100.00%
Senior notes issued price percentage	99.535%	99.535%
5.0% Senior Notes Due 2026 \| Upon the occurrence of certain change of control triggering events
Debt Instrument [Line Items]
Debt instrument redemption price percentage	101.00%
3.8% Senior Notes Due 2028
Debt Instrument [Line Items]
Senior unsecured notes principal amount	$ 1,000,000,000
Senior notes, interest rate	3.80%	3.80%		3.80%	3.80%
Debt instrument redemption price percentage	100.00%
Senior notes issued price percentage	99.747%	99.747%
3.8% Senior Notes Due 2028 \| Upon the occurrence of certain change of control triggering events
Debt Instrument [Line Items]
Debt instrument redemption price percentage	101.00%