Recent Accounting Standards - Summary Impact of ASU 2020-06 on Opening Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Jan. 01, 2021	Dec. 31, 2020
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Deferred tax liabilities (assets)	$ 1,811		$ 8,211
Additional paid-in capital	1,118,761		763,051
Retained earnings	$ 131,419		575,965
Pre-ASU 2020-06
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Deferred tax liabilities (assets)			8,211
Convertible senior notes, net			486,366
Additional paid-in capital			763,051
Retained earnings			$ 575,965
ASU 2020-06
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Deferred tax liabilities (assets)		$ (41,693)
Convertible senior notes, net		148,546
Additional paid-in capital		(107,810)
Retained earnings		957
As Adjusted
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Deferred tax liabilities (assets)		(33,482)
Convertible senior notes, net		634,912
Additional paid-in capital		655,241
Retained earnings		$ 576,922