Stock-Based Compensation (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 5,275,000	$ 4,595,000
SARs \| Named Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	1,650,000
Total stock-based compensation	$ 700,000	0
us-Share-based Compensation Arrangement by Share-based Payment Award, Immediate Award Vesting Rights, Percentage	25.00%
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 3,877,000	3,626,000
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 1,398,000	$ 969,000

Share-based Compensation Arrangement by Share-based Payment Award, Immediate Award Vesting Rights, Percentage

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-Topic 718
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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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Net number of non-option equity instruments granted to participants.

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-Topic 718
-SubTopic 10
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