Income Taxes - Summary of Provision for Income Taxes and U.S. Federal Tax Rate (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount [Abstract]
Computed “expected” tax expense	$ 49,436	$ 61,479
Foreign income tax differential	(3,364)	(2,904)
Excess tax benefit related to stock-based compensation	(13,449)	(10,059)
State taxes net of federal benefits	786	3,324
Foreign-sourced nontaxable income	2,416	(1)
Foreign withholding	3,764	5,150
GILTI, net of foreign tax credits	2,341	2,486
Other	4,663	7,477
Provision for income taxes	$ 46,593	$ 66,952	$ 124,972	$ 119,695
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Computed “expected” tax expense	21.00%	21.00%
Foreign income tax differential	(1.40%)	(1.00%)
Excess tax benefit related to stock-based compensation	(5.70%)	(3.40%)
State taxes net of federal benefits	0.30%	1.10%
Foreign-sourced nontaxable income	1.00%	0.00%
Foreign withholding	1.60%	1.80%
GILTI, net of foreign tax credits	1.00%	0.90%
Other	2.00%	2.50%
Provision for income taxes	19.80%	22.90%

Effective Income Tax Rate Reconciliation, Global Intangible Low Tax Income, Amount

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