Accounting Policies - Cash and Cash Equivalents - Additional Information (Detail)	9 Months Ended
Sep. 30, 2020
Money Market Funds
Cash and Cash Equivalents [Line Items]
Concentration risk, % of money market funds with two issuers	100.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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