Income Taxes

The components of Income (loss) before income taxes are as follows (dollars in thousands):



	Three Months Ended December 31,
	2018			2017
Domestic	$	19,788		$	(34,946	)
Foreign	(1,103		)	3,442
Income (loss) before income taxes	$	18,685		$	(31,504	)

The components of provision (benefit) for income taxes are as follows (dollars in thousands):



	Three Months Ended December 31,
	2018			2017
Domestic	$	834		$	(80,665	)
Foreign	152			1,696
Provision (benefit) for income taxes	$	986		$	(78,969	)
Effective tax rate	5.3		%	250.7		%

The effective tax rates for the three-month periods ended December 31, 2018 and December 31, 2017 were estimated based upon estimated income for the year, the composition of the income in different countries, changes relating to valuation allowances for certain countries if and as necessary, and adjustments, if any, for the potential tax consequences, benefits or resolutions of audits or other tax contingencies. Our aggregate income tax rate in foreign jurisdictions is lower than our income tax rate in the United States; the majority of our income before provision for income taxes from foreign operations has been earned by subsidiaries in Ireland. Our effective tax rate may be adversely affected by earnings being lower than anticipated in countries where we have lower statutory tax rates and higher than anticipated in countries where we have higher statutory tax rates.

Our effective income tax rate was 5.3% for the three months ended December 31, 2018, compared to 250.7% for the three months ended December 31, 2017. The effective tax rate for the three months ended December 31, 2018 differed from the U.S. federal statutory rate of 21% primarily due to the valuation allowance related to losses in the United States. The effective tax rate for the three months ended December 31, 2017 differed from the U.S. federal statutory rate of 24.53% primarily due to the recognition of approximately $96 million estimated deferred tax benefit from the remeasurement of deferred tax assets and liabilities, offset by approximately $14 million estimated tax provision for deemed repatriated foreign earnings, as a result of the Tax Cuts and Jobs Act ("TCJA") enacted in December 2017.

Provision (benefit) for income taxes increased by $80.0 million for the three months ended December 31, 2018 to a provision of $1.0 million for the three months ended December 31, 2018 from a benefit of $79.0 million for the three months ended December 31, 2017, primarily driven by approximately $96 million estimated deferred tax benefit, offset in part by approximately $14 million estimated tax provision for deemed repatriated foreign earnings recognized as a result of the TCJA enacted in December 2017.