As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (12)(c)
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (16)(c)
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 15
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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

Redeemable Noncontrolling Interests - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 30, 2016	Sep. 30, 2016	Dec. 31, 2015
Redeemable Noncontrolling Interest [Line Items]
Incremental stock based compensation charge	$ 49,000
Redeemable noncontrolling interests		$ 1,578,964	$ 658,478
trivago
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests		$ 1,600,000	$ 654,000
trivago \| Window was postpone in the second quarter of 2016 \| Maximum
Redeemable Noncontrolling Interest [Line Items]
Minority shareholders right to sell on remaining shares		50.00%
trivago \| Window opens in 2018 \| Maximum
Redeemable Noncontrolling Interest [Line Items]
Minority shareholders right to sell on remaining shares		100.00%