INCOME TAXES	3 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES Income tax expense consists of U.S. and international income taxes, determined using an estimate of the Company's annual effective tax rate, which is based upon the applicable tax rates and tax laws of the countries in which the income is generated. A deferred tax liability is recognized for all taxable temporary differences, and a deferred tax asset is recognized for all deductible temporary differences and operating loss and tax credit carryforwards. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. The Company considers many factors when assessing the likelihood of future realization of the deferred tax assets, including its recent cumulative earnings experience by taxing jurisdiction, expectations of future income, tax planning strategies, the carryforward periods available for tax reporting purposes, and other relevant factors. The Company's effective tax rate for the three months ended March 31, 2019 was 21.0% compared to 19.4% for the three months ended March 31, 2018. The Company's 2018 effective tax rate differs from the U.S. federal statutory tax rate of 21%, primarily due to the benefit of the Netherlands Innovation Box Tax (discussed below) and current year excess tax benefits recognized from the vesting of equity awards, partially offset by the effect of higher international tax rates and U.S. federal and state tax associated with the Company's current year international earnings, resulting from the introduction of the Tax Act. The Company's effective tax rate was higher for the three months ended March 31, 2019, compared to the three months ended March 31, 2018, primarily as a result of lower excess tax benefits recognized from the vesting of equity awards and higher discrete tax charges related to unrealized gains on equity securities, partially offset by lower U.S. federal and state tax associated with the Company’s current year international earnings, resulting from the introduction of the Tax Act. During the three months ended March 31, 2019 and 2018, a substantial majority of the Company's income was generated in the Netherlands, where Booking.com is based. According to Dutch corporate income tax law, income generated from qualifying innovative activities is taxed at a rate of 7% ("Innovation Box Tax") rather than the Dutch statutory rate of 25%. A portion of Booking.com's earnings during the three months ended March 31, 2019 and 2018 qualified for Innovation Box Tax treatment, which had a significant beneficial impact on the Company's effective tax rate for those periods.

INCOME TAXES

Income tax expense consists of U.S. and international income taxes, determined using an estimate of the Company's annual effective tax rate, which is based upon the applicable tax rates and tax laws of the countries in which the income is generated. A deferred tax liability is recognized for all taxable temporary differences, and a deferred tax asset is recognized for all deductible temporary differences and operating loss and tax credit carryforwards. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. The Company considers many factors when assessing the likelihood of future realization of the deferred tax assets, including its recent cumulative earnings experience by taxing jurisdiction, expectations of future income, tax planning strategies, the carryforward periods available for tax reporting purposes, and other relevant factors.

The Company's effective tax rate for the three months ended March 31, 2019 was 21.0% compared to 19.4% for the three months ended March 31, 2018. The Company's 2018 effective tax rate differs from the U.S. federal statutory tax rate of 21%, primarily due to the benefit of the Netherlands Innovation Box Tax (discussed below) and current year excess tax benefits recognized from the vesting of equity awards, partially offset by the effect of higher international tax rates and U.S. federal and state tax associated with the Company's current year international earnings, resulting from the introduction of the Tax Act.

The Company's effective tax rate was higher for the three months ended March 31, 2019, compared to the three months ended March 31, 2018, primarily as a result of lower excess tax benefits recognized from the vesting of equity awards and higher discrete tax charges related to unrealized gains on equity securities, partially offset by lower U.S. federal and state tax associated with the Company’s current year international earnings, resulting from the introduction of the Tax Act.

During the three months ended March 31, 2019 and 2018, a substantial majority of the Company's income was generated in the Netherlands, where Booking.com is based. According to Dutch corporate income tax law, income generated from qualifying innovative activities is taxed at a rate of 7% ("Innovation Box Tax") rather than the Dutch statutory rate of 25%. A portion of Booking.com's earnings during the three months ended March 31, 2019 and 2018 qualified for Innovation Box Tax treatment, which had a significant beneficial impact on the Company's effective tax rate for those periods.