Amounts Related to eLong in Consolidated Results of Operations (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Pre-tax gain on disposal of business	$ 508,810	$ 508,810
Gain on disposal of business, after-tax	395,000	395,000
eLong, Inc
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Stock-based compensation and intangible amortization	$ 15,000	$ 20,000