Summary of Significant Accounting Policies - Derivative Instruments (Details) € in Millions, $ in Millions	Dec. 31, 2016 EUR (€)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 3,560
Expedia 2.5% Notes
Debt Instrument [Line Items]
Debt Instrument, Face Amount	€ 650	$ 683
Debt Instrument, Interest Rate, Stated Percentage	2.50%	2.50%

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

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