Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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

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- Definition

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

+ References

No definition available.

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Percentage of vesting of share-based compensation awards.

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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.

+ References

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STOCKHOLDERS' DEFICIT - Stock Options (Narrative) (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted	0	0	0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options granted	10 years
Vesting period of options	5 years
Stock Options \| Vest based solely on continued service
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of options	5 years
Options outstanding, vesting percentage	75.00%
Stock Options \| Vest if certain predetermined performance targets are met
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of options	5 years
Options outstanding, vesting percentage	25.00%
Stock Options \| Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options granted	10 years