Income Taxes - Additional Information (Details) - USD ($) $ in Millions			12 Months Ended			24 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018
Income Tax Disclosure [Line Items]
Federal income tax rate	21.00%		35.00%
Percentage of interest expense deduction	30.00%
One-time transition tax on foreign earnings		$ 47		$ 27	$ 48
TRA liability benefit				5	58	$ (55)
Reduction related to certain audit and transfer pricing adjustments			$ 3
Recognized penalties and interest (benefits)			(7)	1	1
Unrecognized tax benefits, including interest and penalty			81	93		93
Cumulative accrued interest and penalties			16	23		23
Unrecognized tax benefits increase			48	55	53
Unrecognized tax benefits that, if recognized, would impact the effective tax rate		$ 70	48	51	$ 70	$ 51
Reasonably possible amount of unrecognized tax benefits may be resolved in the next twelve month			15
lastminute.com
Income Tax Disclosure [Line Items]
Valuation allowance			33	55
Domestic Tax Authority
Income Tax Disclosure [Line Items]
Net operating loss carry forwards			32
State Tax Authority
Income Tax Disclosure [Line Items]
Net operating loss carry forwards			7
Valuation allowance			5	$ 4
State Tax Authority | Research
Income Tax Disclosure [Line Items]
Research tax credit carryforwards			18
Foreign Tax Authority
Income Tax Disclosure [Line Items]
Deferred tax assets for NOL indefinite carry forwards			$ 165
Retained Earnings | ASU 2014-09
Income Tax Disclosure [Line Items]
Cumulative effect adjustment	$ (102)
Deferred Tax Liabilities | ASU 2014-09
Income Tax Disclosure [Line Items]
Cumulative effect adjustment	$ 24