Stock Compensation - Director Stock Grant (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock compensation expense recognized	$ 4,200,000	$ 1,800,000	$ 1,600,000
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining recognition period	2 years
Unrecognized compensation cost	$ 1,800,000
Omnibus Incentive Plan \| Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual restricted shares award (in shares)	57,000
Total stock compensation expense recognized	$ 500,000	$ 500,000	$ 400,000
Remaining recognition period	3 months
Unrecognized compensation cost	$ 100,000

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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Unrecognized cost of unvested share-based compensation awards.

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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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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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Value of shares of stock issued attributable to transactions classified as other.

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