Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Stock-Based Payments - Stock Options (Details)

v3.10.0.1

Stock-Based Payments - Stock Options (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted and outstanding (in shares)	1,548,252
Aggregate Intrinsic Value
Intrinsic value of options exercised	$ 1.4	$ 4.6	$ 2.4
Cash received from option exercises	0.6	$ 1.8	$ 0.4
Performance-based stock options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional stock-based compensation expense recorded related to achievement of certain performance-based milestones	0.2
Unrecognized compensation costs	$ 1.0
Period in which compensation costs will be recognized	3 years 9 months 18 days
Performance-based stock options \| Advisor
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation costs	$ 0.3
Period in which compensation costs will be recognized	7 years 8 months 12 days
Granted and outstanding (in shares)	75,000

- Definition

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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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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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

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