v3.8.0.1

Summary of Significant Accounting Policies - Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of Significant Accounting Policies
Defined contribution plan, Employer discretionary contributions	$ 0.3	$ 0.3	$ 0.0

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- References

No definition available.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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