Quantitative information regarding the Stock Options and Stock Grants: (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Stock options granted	10,000	535,000
Stock options exercised	367,000	78,277
Proceeds to Nanophase from exercises	$ 152	$ 23
Stock options forfeited	34,500	202,134
Stock option expirations	220,800	460,640
Stock options outstanding	2,833,650	3,507,073
Weighted average exercise price per share	$ 0.55	$ 0.58

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Number of non-vested options outstanding.

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 718
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