Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 895,073	[1],[2]	$ 811,483	$ 740,200	[3],[4]
Other comprehensive (loss) income:
Foreign currency translation (losses) gains, net of tax	(15,855)		(362,001)	83,165
Reclassification of foreign currency translation loss to investment, net of tax	0		0	31,381
Net change in derivative contracts, net of tax	(42,752)		0	0
Total other comprehensive (loss) income	(58,607)		(362,001)	114,546
Total comprehensive income	$ 836,466		$ 449,482	$ 854,746

[1] Reflects the impact of the Company's adoption of ASU 2016-02 "Leases", on January 1, 2019 using the modified retrospective transition method. The adoption of the Leases guidance resulted in an adjustment to other assets, other current liabilities and other noncurrent liabilities in our consolidated balance sheet for the cumulative effect of applying the standard. Financial results reported in periods prior to 2019 are unchanged.

[2] Reflects the impact of the Company's adoption of ASU 2016-02 "Leases", on January 1, 2019, using a modified retrospective transition method. Under this method, financial results reported in periods prior to 2019 are unchanged. Refer to footnote 14.

[3] Reflects the impact of the Company's adoption of Accounting Standards Update 2016-18, Statement of Cash Flows (Topic 230), which was adopted by the Company on January 1, 2018 and applied retrospectively to results for 2017. The adoption of Topic 230 resulted in the statement of cash flows presenting the changes in the total of cash, cash equivalents and restricted cash. As a result, the Company will no longer present transfers between cash and cash equivalents and restricted cash in the statement of cash flows.

[4] The Company applied the modified retrospective transition method when adopting ASC 606, therefore the Company's 2017 prior period results were not restated to reflect ASC 606.