Income taxes.

No definition available.

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Estimated potential increase in income tax expense for tax years of 2009, 2010 and 2011 IRS audits based on received NOPA's from IRS.

+ References

No definition available.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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Income Taxes - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 31, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Income tax expense at federal statutory rate				21.00%		35.00%
Effective tax rate		50.00%	23.80%	40.60%	42.90%
Cumulative income tax expense recorded upon non-Company related litigation		$ 15,000,000
Accrued interest liability		18,000,000		$ 18,000,000
Accrued penalties		$ 0		$ 0
Minimum \| Expedia \| IRS \| Tax Years 2009 and 2010
Income Taxes [Line Items]
Increase in income tax expense due to proposed adjustments related to transfer pricing with foreign subsidiary, estimated	$ 15,000,000
Maximum \| Expedia \| IRS \| Tax Years 2009 and 2010
Income Taxes [Line Items]
Increase in income tax expense due to proposed adjustments related to transfer pricing with foreign subsidiary, estimated	$ 20,000,000