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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.

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Disclosure of information about 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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Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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

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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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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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Percentage of vesting of award under share-based payment arrangement.

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STOCK AWARD PLAN AND STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	6 Months Ended	9 Months Ended
	Aug. 06, 2021	Jun. 11, 2021	Dec. 31, 2017	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Common stock, shares issued					42,721,566		42,721,566
Fair value of common stock on grant date (in dollars per share)					$ 3.13
Total intrinsic value of the stock options exercised					$ 0.0	$ 0.9
Dividend yield (as a percent)					0.00%
Employee Stock Option
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Fair value of common stock on grant date (in dollars per share)					$ 1.83	$ 1.62
Dividend yield (as a percent)					0.00%	0.00%
Restricted Stock Units
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Vesting percentage					25.00%
Vesting period of PRSUs after acceptance					4 years
Description of vesting rights					RSUs awarded to employees generally vest one-fourth per year over four years from the anniversary of the date of grant
Performance Based Restricted Stock Units
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Shares issued	3,813,150
Total unrecognized compensation costs					$ 4.5
Weighted-average period over which unrecognized compensation costs is expected to be recognized					1 year 7 months 6 days
Granted (in shares)	3,813,150
Stock Option Awards [Member]
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Cancellation of company's common stock					7,631,844
Total unrecognized compensation costs					$ 1.5
Weighted-average period over which unrecognized compensation costs is expected to be recognized					1 year 2 months 12 days
Option Exchange Program [Member]
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Non-cash incremental stock-based compensation cost					$ 0.5
Common stock, shares issued	7,631,844
Common stock exchanged for PRSUs	3,813,150
Option Exchange Program [Member] \| Performance Based Restricted Stock Units
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Exercise price per unit		$ 4.47
Vesting percentage		50.00%
Option Exchange Program [Member] \| Performance Based Restricted Stock Units \| U S Food and Drug Administration [Member] \| Minimum [Member]
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Vesting period of PRSUs after acceptance		3 years
Option Exchange Program [Member] \| Performance Based Restricted Stock Units \| U S Food and Drug Administration [Member] \| Maximum [Member]
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Vesting period of PRSUs after acceptance		5 years
2013 Equity Incentive Plan \| Common Stock
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Increase in number of shares authorized for issuance				2,000,000
2013 Equity Incentive Plan \| Employee Stock Option \| Common Stock \| Rick Russell
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Shares issued			775,000
Granted (in shares)			775,000
2013 Equity Incentive Plan \| Restricted Stock Units \| Common Stock \| Rick Russell
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Shares issued			40,000
Granted (in shares)			40,000