Equity Awards - Restricted Stock Units Narrative (Details) - Restricted Stock Units [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares issued related to director fee deferrals	1,781
Number of Unvested Restricted Stock Units Granted	40,096
Unrecognized unvested restricted shares-based compensation expense	$ 5.8
Weighted-average period for recognition of the unrecognized unvested restricted shares-based compensation expense	1 year 11 months
Total shareholder return metric [Member] \| Plan 3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Unvested Restricted Stock Units Granted	38,315
Share-based Compensation Arrangement by Share-based Payment Award, Award percentage attained		139.00%
Total shareholder return metric [Member] \| Minimum [Member] \| Plan 3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Amount of shares earned % of target award	0.00%
Total shareholder return metric [Member] \| Maximum [Member] \| Plan 3 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Amount of shares earned % of target award	200.00%
Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares-based compensation expense	$ 1.3	$ 1.1

Amount of shares earned as a % of target award.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award percentage attained

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No definition available.

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- Definition

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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- Definition

Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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- Definition

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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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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- 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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