Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Loss Before Provision for Income Taxes by Country

Income (loss) before provision for income taxes by country for each of the fiscal periods presented is summarized as follows (in thousands):

	Year Ended December 31,
	2017			2016			2015
Ireland	$	(162,865	)	$	(164,797	)	$	(83,009	)
Switzerland	480			—			—
U.S.	4,782			5,833			3,098
Loss before provision for income taxes	$	(157,603	)	$	(158,964	)	$	(79,911	)

Components of the Provision for Income Taxes

Components of the provision for income taxes for each of the fiscal periods presented consisted of the following (in thousands):

	Year Ended December 31,
	2017			2016			2015
Current:
U.S. Federal	$	(2,478	)	$	4,464		$	1,663
U.S. State	1			1			1
Switzerland	306			—			—
Ireland	5			—			—
Total current provision	$	(2,166	)	$	4,465		$	1,664
Deferred:
U.S. Federal	$	(2,200	)	$	(3,321	)	$	(963	)
U.S. State	—			—			—
Switzerland	—			—			—
Ireland	—			—			—
Total deferred benefit	(2,200		)	(3,321		)	$	(963	)
Total provision for income taxes	$	(4,366	)	$	1,144		$	701

Reconciliation Between Income Taxes Computed at the Standard Irish Statutory Tax Rate and the Provision for income Taxes

ollowing is a reconciliation between income taxes computed at the Irish statutory tax rate and the provision for income taxes for each of the fiscal periods presented (in thousands):

	Years Ended December 31,
	2017			2016			2015
Taxes at the Irish statutory tax rate of 12.5%	$	(19,700	)	$	(19,870	)	$	(9,989	)
Income tax at rates other than applicable statutory rate	678			813			446
Change in valuation allowance	28,967			25,200			12,594
Share-based payments	(8,242		)	422			214
Tax credits	(5,857		)	(5,384		)	(2,712		)
Other	(212		)	(37		)	148
Provision for (benefit from) income taxes	$	(4,366	)	$	1,144		$	701

Significant Components of Net Deferred Tax Assets

Significant components of the Company’s net deferred tax assets as of December 31, 2017 and 2016 are as follows (in thousands):

	December 31,
	2017			2016
Deferred tax assets:
Net operating losses	$	67,653		$	47,218
Tax credits	16,308			4,937
Accruals	1,285			1,322
Share-based compensation	7,444			8,966
Gross deferred tax assets	92,690			62,443
Valuation allowance	(83,972		)	(56,382		)
Net deferred tax assets	8,718			6,061
Deferred tax liability:
Fixed Assets	(605		)	(148		)
Net deferred tax assets	$	8,113		$	5,913

Summary of Income Tax Contingencies

A reconciliation of the beginning and ending amounts of unrecognized tax benefits is as follows (in thousands):

	2017		2016
Gross Unrecognized Tax Benefits at January 1	$	2,406	$	1,061
Additions for tax positions taken in the current year	1,464		1,346
Additions for tax positions taken in the prior year	398		—
Reductions for tax positions taken in the prior year	—		(1		)
Gross Unrecognized Tax Benefits at December 31	$	4,268	$	2,406