Conversion of shares of one class into another.

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Unamortized stock-based compensation for stock options

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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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.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of options vested.

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Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

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Incentive Shares and Share/Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	May 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance		6,948,647
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares		4,719,605
Share-based compensation expense		$ 13,321	$ 526	$ 111
Unvested Restricted Stock And Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement unrecognized compensation		$ 56,300
Share based compensation by share based payment arrangement unrecognized compensation remaining period for recognition		2 years 7 months 6 days
Weighted-average period expected to be recognized		3 years 10 months 24 days
Unamortized stock-based compensation for stock options		$ 2,100
Incentive Share Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement term of vesting		4 years
Share based compensation by share based payment award fair value assumptions dividend yield		0.00%
Total fair value of options		$ 1,100
Weighted-average grant date fair value of options granted		$ 9.91
Weighted-average period expected to be recognized		2 years 6 months
Unamortized stock-based compensation for stock options		$ 41,100
Incentive Share Plan [Member] \| Day One Holding LLC [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangment number of shares authorized		8,924,177
Incentive Share Plan [Member] \| Day One Holding LLC [Member] \| Cliff Vesting
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement term of vesting		12 months
Two Thousand And Twenty One Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Conversion of shares of one class into another		5,433,290
Two Thousand And Twenty One Stock Incentive Plan \| Unvested Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Conversion of shares of one class into another		4,719,605
Two Thousand And Twenty One Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment award fair value assumptions dividend yield		0.00%
Common Stock, Capital Shares Reserved for Future Issuance	6,369,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares	4,719,605
Total intrinsic value of the options outstanding		$ 3,756
Weighted average remaining contractual term		9 years 4 months 24 days
Two Thousand And Twenty One Equity Incentive Plan \| Unvested Restricted Stock And Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement term of vesting		4 years
Two Thousand And Twenty One Equity Incentive Plan \| Incremental Shares Reserved For Future Issuance
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum	5.00%
Two Thousand And Twenty One Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	603,000
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum	1.00%
Stock Issued During Period, Shares, Employee Stock Ownership Plan		23,353
Share-based compensation expense		$ 200