Number of new stock issued during the period.

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-Topic 210
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-Name Accounting Standards Codification
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Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Commitments and Contingencies - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	Nov. 01, 2019	Sep. 30, 2020
Loss Contingencies [Line Items]
Stock issued during period, shares, new issues (in shares)	14.4
Maximum
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss		$ 5.0