Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit.

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The difference between the carrying value and the sale price of an investment. A loss would be recognized when the sale price of the investment is less than the carrying value of the investment. This element refers to the Loss included in earnings and not to the cash proceeds of the sale.

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Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Oct. 01, 2016	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale investments, short-term			$ 0	$ 48,000
Available for sale investments, long-term			0	16,000
Gross unrealized gains				1,000
Gross unrealized losses				1,000
Net gains(losses) from foreign currency forward contracts			17,000	(66,000)	$ 46,000
Foreign currency forward contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional amount of foreign currency derivatives			2,600,000
Recurring Basis \| Foreign currency forward contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency forward contracts, Assets			6,141
Foreign currency forward contracts, Liabilities				4,402
Nonrecurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of indefinite-lived intangible assets					$ 7,000
Cost method investments			371,000	323,000
Loss on cost method investments			(14,000)
Other than temporary impairment of cost method investments			6,000	12,000
Loss on sale of cost method Investments			9,000
Fair value of cost method investments				1,000
Nonrecurring Basis \| Trade Names
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of indefinite-lived intangible assets	$ 33,000	$ 2,000		35,000
Fair value of indefinite-lived intangible assets				$ 76,000
Despegar.com Corp. \| Available-for-sale Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized cost			273,000
Accumulated gross unrealized loss			$ 9,000