Stock options, strike price description.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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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- Definition

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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No definition available.

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- Definition

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

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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STOCK-BASED COMPENSATION (Details Narrative) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Feb. 19, 2019	Sep. 28, 2018	Dec. 31, 2021	Dec. 31, 2020	Jun. 10, 2021	Jun. 15, 2020	May 14, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Issued			5,770,538	2,713,424
Unrecognized compensation cost			$ 1.7
Cost recognized over a weighted-average period			1 year
Equity Stock Awards [Member] \| Granted Under 2018 Plan and 2007 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance			433,676
Inducement Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance			9,332
Stock Options and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost			$ 3.8	$ 1.9
Stock Options and Restricted Stock Awards [Member] \| Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost			1.4	0.8
Stock Options and Restricted Stock Awards [Member] \| General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost			$ 2.4	$ 1.1
Common Stock, Shares Issued				429,855
2018 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			180,000
Common Stock, Capital Shares Reserved for Future Issuance			946,561
2018 Stock Incentive Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Available for Grant					513,333	166,667	80,000
2018 Stock Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Available for Grant					940,000	426,667	260,000
2007 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, strike price description			Options are generally granted with strike prices equal to the fair market value of a share of Celsion common stock on the date of grant. Incentive stock options may be granted to purchase shares of common stock at a price not less than 100% of the fair market value of the underlying shares on the date of grant, provided that the exercise price of any incentive stock option granted to an eligible employee owning more than 10% of the outstanding stock of Celsion must be at least 110% of such fair market value on the date of grant. Only officers and key employees may receive incentive stock options.
Inducement Option Grants [Member] \| Five New Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price per share	$ 32.70	$ 41.55
Award Vesting Period	3 years
Inducement Option Grants [Member] \| Five New Employees [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Issued	8,666	1,266
Inducement Option Grants [Member] \| Five New Employees [Member] \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Issued	9,332	10,933
2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance			512,884