Stock-Based Compensation - Additional Information (Detail) - $ / shares shares in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted	0	0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock options and restricted stock	3 years
Contractual terms	10 years
Stock-based compensation plans, number of additional shares authorized for future grants	1,098
Closing price per share of Digimarc common stock	$ 13.05
Restricted Stock [Member] \| Minimum [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock options and restricted stock	3 years
Restricted Stock [Member] \| Minimum [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock options and restricted stock	1 year
Restricted Stock [Member] \| Maximum [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock options and restricted stock	4 years
Restricted Stock [Member] \| Maximum [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock options and restricted stock	3 years

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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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

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- Definition

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

+ References

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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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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