Commitments and Contingencies (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Other Commitments [Line Items]
Unemployment benefits, possible liability with a change in control	$ 33.0
Unemployment benefits, possible liability without a change in control	$ 13.4
Minimum
Other Commitments [Line Items]
Period for providing minimum compensation salary and continuation of certain benefits to executives under employment agreements	6 months
Severance payment as a percentage of annual salary	100.00%
Severance payment as a percentage of annual bonus	50.00%
Maximum
Other Commitments [Line Items]
Period for providing minimum compensation salary and continuation of certain benefits to executives under employment agreements	3 years
Severance payment as a percentage of annual salary	300.00%
Severance payment as a percentage of annual bonus	300.00%

Employment Agreement, Severance, Percentage of Annual Bonus

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Employment Agreement, Severance, Percentage of Annual Salary

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- Definition

Period for continuation of minimum compensation and benefits under certain executive employee agreements.

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- Definition

Supplemental unemployment benefits for employees under contract that are terminated without good cause or the employee resigns for good reason following a change in control.

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Supplemental unemployment benefits for employees under contract that are terminated without good cause or the employee resigns for good reason in the absence of a change in control.

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No definition available.

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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.

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