Note 2 - Fair Value of Financial Instruments - Summary of Fair Value Maturities for Financial Asset (Details) $ in Thousands	Mar. 31, 2023 USD ($)
Assets, fair value	$ 41,121
Cash equivalents and marketable securities, less than 1 year	41,121
Cash equivalents and marketable securities, 5-10 years	0
Cash equivalents and marketable securities, more than 10 years	$ 0

Cash equivalents and marketable securities maturity less than one year, fair value.

No definition available.

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- Definition

Cash equivalents and marketable securities maturity more than ten year, fair value.

+ References

No definition available.

+ Details

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- Definition

Cash equivalents and marketable securities maturity year five through ten year, fair value.

+ References

No definition available.

+ Details

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Namespace Prefix:	dmrc_
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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

+ Details

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