Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2020	Jan. 01, 2019	Jan. 01, 2018	Dec. 31, 2017
Significant Accounting Policy [Line Items]
Accounts receivable, allowance for credit loss	$ 5,579	$ 11,143	$ 15,345
Operating lease, right-of-use asset	432,723	390,035
Operating lease, liability	438,189
Cumulative adjustment for adoption of new accounting pronouncement	2,663,227	2,197,219	1,987,720				$ 1,994,373
Deferred contract costs	327,448	131,783
Contract liabilities	379,722	154,183
Net foreign currency gains (losses)	(25,398)	(9,251)	(1,853)
Retained earnings
Significant Accounting Policy [Line Items]
Cumulative adjustment for adoption of new accounting pronouncement	$ 2,600,201	2,321,316	$ 2,088,707				2,063,512
Cumulative Effect, Period of Adoption, Adjustment
Significant Accounting Policy [Line Items]
Cumulative adjustment for adoption of new accounting pronouncement		6,074					(22,462)
Cumulative Effect, Period of Adoption, Adjustment | Retained earnings
Significant Accounting Policy [Line Items]
Cumulative adjustment for adoption of new accounting pronouncement		$ 6,074					$ (22,357)
Accounting Standards Update 2016-13 | Cumulative Effect, Period of Adoption, Adjustment
Significant Accounting Policy [Line Items]
Accounts receivable, allowance for credit loss				$ (8,000)
Cumulative adjustment for adoption of new accounting pronouncement				$ 6,000
Accounting Standards Update 2016-02
Significant Accounting Policy [Line Items]
Operating lease, right-of-use asset					$ 343,000
Operating lease, liability					$ 340,000
Accounting Standards Update 2014-09 | Cumulative Effect, Period of Adoption, Adjustment
Significant Accounting Policy [Line Items]
Deferred contract costs						$ 135,000
Contract liabilities						165,000
Accounting Standards Update 2014-09 | Cumulative Effect, Period of Adoption, Adjustment | Retained earnings
Significant Accounting Policy [Line Items]
Cumulative adjustment for adoption of new accounting pronouncement						$ 22,000