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Weighted Average Assumptions Used to Value Stock-Based Awards (Detail) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock-based compensation, expected dividend yield | 0.00% |  |
Stock Options |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Expected term (in years) | 6 years 9 months 25 days | 6 years 11 months 19 days | 6 years 10 months 20 days
Estimated volatility | 55.00% | 55.00% | 52.00%
Risk-free interest rate | 1.89% | 1.16% | 0.94%
Stock-based compensation, expected dividend yield | 0.00% | 0.00% | 0.00%
Employee Stock Purchase Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Expected term (in years) | 8 months 26 days | 8 months 26 days | 8 months 19 days
Estimated volatility | 56.00% | 56.00% | 53.00%
Risk-free interest rate | 2.25% | 0.07% | 0.86%
Stock-based compensation, expected dividend yield | 0.00% | 0.00% | 0.00%

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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Details
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