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Stock-Based Compensation - Assumptions Used to Compute Share-Based Compensation Costs for Stock Options Granted (Detail) - $ / shares | 6 Months Ended | 12 Months Ended
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Sep. 30, 2021 | Mar. 31, 2021 | Sep. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2021 | Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |  |  |  |  |  |
Weighted average grant date fair value of stock options |  |  |  |  | $ 5.94 | $ 2.93
Assumptions |  |  |  |  |  |
Risk-free interest rate (weighted average) | 0.05% | 0.12% | 0.29% | 1.84% | 0.87% | 0.44%
Weighted average expected life (years) | 6 months | 6 months | 6 months | 6 months | 6 years 2 months 12 days | 6 years 2 months 12 days
Volatility (weighted average) | 44.60% | 47.10% | 86.80% | 86.30% | 74.50% | 80.80%
Forfeiture rate |  |  |  |  | 12.00% | 12.00%

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- Definition Share based compensation arrangement by share based payment award fair value assumptions weighted average forfeiture rate. + References No definition available. + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Rate of weighted-average expected volatility for award under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809 + Details
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