Commitments and Contingencies - Employment Agreements (Details)	12 Months Ended
Dec. 31, 2018 USD ($)
Kasbar agreement
Loss contingencies
Annual base salary	$ 900,000
Agreement expiration term, extension under specified condition	1 year
Minimum period prior to expiration of the term for serving specified notice to prevent extension of the agreement term	1 year
Severance payment for termination following a change of control	$ 5,000,000.0
Severance payment for termination following other scenarios	$ 3,000,000.0
Vesting period of outstanding equity awards	2 years
Period for severance payment after termination of executive's employment	2 years
Agreements with executive officers and key employees
Future minimum commitments under agreements with executive officers and key employees
2018	$ 900,000

No definition available.

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- Definition

The amount of commitment expense expected to be paid during year one of the five succeeding fiscal years.

+ References

No definition available.

+ Details

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- Definition

Represents the term of extension in the expiration period of the agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum period prior to expiration of the term for serving the specified notice to prevent extension of the agreement term.

+ References

No definition available.

+ Details

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- Definition

Represents the annual base salary under the agreement.

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No definition available.

+ Details

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- Definition

Represents the period for severance payment after termination of the executive's employment under the agreement.

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No definition available.

+ Details

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- Definition

Represents the amount of severance payment for termination of the executive's employment following a change in control under the agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of severance payment for termination of the executive's employment following other scenarios.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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