Income Taxes

6 Months Ended

Jun. 30, 2021

Income Tax Disclosure [Abstract]

Income Taxes

Income Taxes

The Company's tax provision or benefit from income taxes for interim periods is determined using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period. Each quarter the Company updates the estimate of the annual effective tax rate, and if our estimated tax rate changes, makes a cumulative adjustment. The Company's quarterly tax provision and quarterly estimate of the annual effective tax rate are subject to significant variation due to several factors, including variability in accurately predicting the pre-tax and taxable income and loss and the mix of jurisdictions to which they relate. Additionally, the Company's effective tax rate can be more or less volatile based on the amount of pre-tax income or loss. For example, the impact of discrete items and non-deductible expenses on our effective tax rate is greater when our pre-tax income is lower.

The provision for income taxes differs from amounts computed by applying the U.S. federal tax rate of 21% for 2021 and 2020 to income before income taxes for the three months ended June 30, 2021 and 2020 due to the following (in thousands):

	2021				2020
Computed “expected” tax expense	$	55,129	21.0	%	$	44,443	21.0	%
Changes resulting from:
Foreign income tax differential	(3,899)		(1.5)	%	(4,155)		(2.0)	%
Excess tax benefit related to stock-based compensation	(6,059)		(2.3)	%	(12,720)		(6.0)	%
State taxes net of federal benefits	2,949		1.1	%	3,902		1.8	%
Change in UK statutory rate	6,470		2.5	%	—		—	%
Foreign withholding	(316)		(0.1)	%	3,515		1.7	%
GILTI, net of foreign tax credits	2,899		1.1	%	2,402		1.1	%
Foreign sourced non taxable income	50		—	%	13		—	%
Change in taxes for federal uncertain tax positions	4,800		1.8	%	12,261		5.8	%
Other	4,249		1.6	%	3,479		1.7	%
Provision for income taxes	$	66,272	25.2	%	$	53,140	25.1	%