Stock-Based Compensation (Additional Information Related to Stock Options) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of share-based awards exercised	$ 16	$ 28	$ 36

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.

No definition available.

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