Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
ASU 2018-07
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accounting standard update adopted	true
Accounting standard update material impact	true
Accounting standard update adoption date	Jan. 01, 2020
Additional Paid-in Capital
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
IPO-related costs	$ 3.4
Other Assets
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Deferred offering costs		$ 1.1