Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award
Share-based compensation expense, tax benefit recognized	$ 0.0	$ 0.0
Closing Stock Price	$ 6.36
Common shares under option plans
Share Based Compensation Arrangement By Share Based Payment Award
Unrecognized stock-based compensation expense related to unvested stock options	$ 32.3
Unrecognized stock-based compensation expense related to non-vested options and/or RSUs, weighted-average remaining vesting period	1 year 10 months 24 days
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award
Unrecognized stock-based compensation expense related to unvested RSUs	$ 57.0
Unrecognized stock-based compensation expense related to non-vested options and/or RSUs, weighted-average remaining vesting period	2 years 6 months

Closing value of stock at end of reporting period.

No definition available.

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

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

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