Debt - Fair Value of Outstanding Debt (Details)	Sep. 30, 2016 USD ($)	Sep. 30, 2016 EUR (€)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 EUR (€)
7.456% Senior Notes Due 2018
Debt Instrument [Line Items]
Fair value of senior notes	$ 550,000,000		$ 555,000,000
Debt, interest rate (percentage)	7.456%	7.456%	7.456%	7.456%
Senior unsecured notes principal amount	$ 500,000,000
5.95% Senior Notes Due 2020
Debt Instrument [Line Items]
Fair value of senior notes	$ 849,000,000		$ 827,000,000
Debt, interest rate (percentage)	5.95%	5.95%	5.95%	5.95%
Senior unsecured notes principal amount	$ 750,000,000
2.5% Senior Notes Due 2022
Debt Instrument [Line Items]
Fair value of senior notes	$ 776,000,000	€ 691,000,000	$ 705,000,000	€ 644,000,000
Debt, interest rate (percentage)	2.50%	2.50%	2.50%	2.50%
Senior unsecured notes principal amount \| €		€ 650,000,000		€ 650,000,000
4.5% Senior Notes Due 2024
Debt Instrument [Line Items]
Fair value of senior notes	$ 528,000,000		$ 487,000,000
Debt, interest rate (percentage)	4.50%	4.50%	4.50%	4.50%
Senior unsecured notes principal amount	$ 500,000,000
5.0% Senior Notes Due 2026
Debt Instrument [Line Items]
Fair value of senior notes	$ 792,000,000		$ 750,000,000
Debt, interest rate (percentage)	5.00%	5.00%	5.00%	5.00%
Senior unsecured notes principal amount	$ 750,000,000

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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

- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13476-108611

+ Details

Name:	us-gaap_DebtInstrumentFairValue
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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ 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

- 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_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: