Other disclosures

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Share based compensation arrangement by share based payment award minimum exercise price of options granted to employees with more than 10 percentage of common stock.

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No definition available.

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Represents the minimum percentage of ownership required for granting of options at a price not less than 110 percent of the fair market value of common stock.

+ References

No definition available.

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- Definition

Aggregate Intrinsic Value

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No definition available.

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- Definition

Represents the number of options to be granted to purchase shares in each year during the optionee's service on the Board of Directors.

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No definition available.

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- Definition

Represents the number of options to be granted to purchase shares upon appointment to Board of Directors.

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No definition available.

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- Definition

Represents the maximum expiration term of options granted to employees having more than 10 % outstanding common stock.

+ References

No definition available.

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Aggregate number of common shares reserved for future issuance.

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

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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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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

+ References

No definition available.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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

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No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

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- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

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STOCKHOLDERS' EQUITY - EQUITY PLANS (Details) - USD ($)	12 Months Ended
STOCKHOLDERS' EQUITY - EQUITY PLANS (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Feb. 29, 2020	Jan. 31, 2019	Oct. 31, 2018	May 15, 2018
STOCKHOLDERS' EQUITY
Common stock, shares reserved for future issuance (in shares)	45,395,620
Aggregate Intrinsic Value - Options Outstanding
Closing stock price (in dollars per share)	$ 1.36
Total pretax intrinsic value of stock options exercised (in dollars)	$ 80,000	$ 8,812,000	$ 15,000
Cash received from exercise of options (in dollars)	$ 163,000	$ 6,929,000	$ 18,000
Number of Shares - Options Outstanding
Options exercisable at the end of the period (in shares)	19,915,713	16,464,746	17,249,032
Weighted Average Exercise Price Per Share - Options Outstanding
Options exercisable at the end of the period (in dollars per share)	$ 2.86	$ 3.13	$ 3.03
2002 Plan
STOCKHOLDERS' EQUITY
Vesting period of options	4 years
Exercise price as a percentage of fair market value	100.00%
2002 Plan \| Maximum
STOCKHOLDERS' EQUITY
Expiration term of options from date of grant	10 years
2011 Plan
STOCKHOLDERS' EQUITY
Vesting period of options	4 years
2011 Plan \| Restricted stock awards
STOCKHOLDERS' EQUITY
Shares issued (in shares)			72,066
Weighted Average Grant Date Fair Value Per Share
Granted (in dollars per share)			$ 2.20
Other disclosures
Total fair value of restricted stock that vested			$ 159,000
2011 Plan \| Maximum
STOCKHOLDERS' EQUITY
Expiration term of options from date of grant	10 years
2018 Plan
STOCKHOLDERS' EQUITY
Vesting period of options	4 years
Common stock, shares reserved for future issuance (in shares)							10,000,000
Minimum percentage of ownership required for granting options at least 110% of fair market value of common stock	10.00%
Minimum exercise price as a percentage of fair market value for employees having more than 10 % outstanding common stock	110.00%
Maximum expiration term of options granted to employees having more than 10 % outstanding common stock	5 years
2018 Plan \| First Director Option
STOCKHOLDERS' EQUITY
Vesting period of options	3 years
Options to be granted to purchase shares upon appointment (shares)	120,000
2018 Plan \| Subsequent Director Option
STOCKHOLDERS' EQUITY
Options to be granted to purchase shares (in shares)	70,000
2018 Plan \| Restricted stock awards
STOCKHOLDERS' EQUITY
Shares issued (in shares)		73,980
Weighted Average Grant Date Fair Value Per Share
Granted (in dollars per share)		$ 1.91
Other disclosures
Total fair value of restricted stock that vested		$ 141,000
2018 Plan \| Maximum
STOCKHOLDERS' EQUITY
Expiration term of options from date of grant	10 years
2006 Directors Plan \| First Director Option
STOCKHOLDERS' EQUITY
Vesting period of options	3 years
2006 Directors Plan \| Subsequent Director Option
STOCKHOLDERS' EQUITY
Vesting period of options	1 year
2006 Directors Plan \| Maximum
STOCKHOLDERS' EQUITY
Expiration term of options from date of grant	10 years
2018 Inducement Award Plan
STOCKHOLDERS' EQUITY
Common stock, shares reserved for future issuance (in shares)		3,000,000			8,000,000
2018 Inducement Award Plan \| Subsequent Event
STOCKHOLDERS' EQUITY
Common stock, shares reserved for future issuance (in shares)				9,300,000
Directors’ Market Value Stock Purchase Plan
STOCKHOLDERS' EQUITY
Common stock, shares reserved for future issuance (in shares)						1,000,000
Directors’ Market Value Stock Purchase Plan \| Restricted stock awards
STOCKHOLDERS' EQUITY
Shares issued (in shares)	29,150
Weighted Average Grant Date Fair Value Per Share
Granted (in dollars per share)	$ 1.50
Other disclosures
Total fair value of restricted stock that vested	$ 44,000