Stock-Based Compensation - Additional Information (Detail) shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020 $ / shares shares	Jun. 30, 2020 $ / shares shares
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		1,071
Closing price per share of Digimarc common stock \| $ / shares	$ 15.99	$ 15.99
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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Number of additional shares authorized for issuance under share-based payment arrangement.

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

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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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