Aggregate number of common shares reserved for future issuance.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Gross number of share options (or share units) granted during the period.

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Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

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No definition available.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of non-vested options outstanding.

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- Definition

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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- Definition

Common stock capital shares reserved for future issuance additions.

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Share based compensation arrangement by share based payment award award vesting rights remaining spread in quarters.

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Stock-Based Compensation - Additional Information (Detail)		12 Months Ended
	Sep. 30, 2021 USD ($) shares	Dec. 31, 2021 USD ($) Quarters shares	Dec. 31, 2020 shares	Dec. 31, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Granted		1,662,897
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award equity instruments granted		133,384
Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount \| $		$ 914,000
Cost Expected to be Expensed, Weighted Average Period		3 years 9 months 18 days
Restricted Stock Units (RSUs) [Member] \| Related Parties [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award equity instruments granted		7,398	0	0
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Accelerated Vesting, Number	814,272
Unrecognized Compensation Costs \| $		$ 13,853,000
Cost Expected to be Expensed, Weighted Average Period		2 years 8 months 12 days
Share-based Payment Arrangement, Option [Member] \| Merger and Acquisition Transaction [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs \| $		$ 7,281,000
Cost Expected to be Expensed, Weighted Average Period		2 years 3 months 18 days
Number Of Outstanding Options Unvested		2,300,980
Share-based Payment Arrangement, Option [Member] \| Related Parties [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Granted		321,777	3,347,705	1,003,185
Share-based Payment Arrangement, Option [Member] \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Accelerated Cost \| $	$ 3,396,000
Valens Semiconductor Ltd. 2021 Share Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based Payment Award, Expiration Period		10 years
Sharebased Payment Award, Vesting Rights Percentage		25.00%
Share based Payment Award, Vesting Rights Remaining Spread In Quarters \| Quarters		12
Common stock capital shares reserved for future issuance additions		8,370,000	2,318,860
Ordinary Shares, Reserved For Issuance		28,383,788	20,013,788