Preparation of Interim Financial Statements and Other Items - Stock-based Compensation (Details - Restricted Stock Units - USD ($) $ / shares in Units, $ in Millions				3 Months Ended	9 Months Ended
Sep. 21, 2018	May 31, 2018	Feb. 12, 2018	Sep. 30, 2018	Sep. 30, 2018
Stock-based Compensation
Granted (in shares)	5,450	29,656	737,493
Grant date fair value (in dollars per share)	$ 36.70	$ 33.72	$ 19.00
Vesting period	3 years	7 years	3 years
Compensation expenses				$ 1.3	$ 3.4
Unrecognized compensation cost				$ 11.8	$ 11.8
Expected to be recognized over weighted average period					2 years 8 months 12 days

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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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.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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