Goodwill and Other Intangible Assets - Components of Goodwill and Other Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill	$ 380,687	$ 383,861	$ 368,069	$ 371,773
Other intangible assets (net of accumulated amortization)	180	210
Goodwill and other intangible assets, Total	$ 380,867	$ 384,071