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Net Income Per Common Share - Additional Information (Detail) - shares shares in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2018
Employee Stock Option [Member] |  |
Net Income Loss Per Common Share |  |
Exercise of stock options | 0.1 |
Restricted Stock Units (RSUs) [Member] |  |
Net Income Loss Per Common Share |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 0.1 | 0.5

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- Definition Net Income (Loss) Per Common Share [Line Items] + References No definition available. + Details
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- Definition Stock issued during period shares sale of stock and exercise of stock options. + References No definition available. + Details
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Details
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