Share-Based Compensation (Narrative) (Details)	3 Months Ended
Mar. 31, 2019 USD ($)
Employee Stock Options
Unrecognized compensation cost related to share-based compensation	$ 1,400,000
Weighted-average service period, years	2 years 36 days
Restricted Stock Rights
Unrecognized compensation cost related to share-based compensation	$ 456,000
Weighted-average service period, years	2 years 36 days
PSU
Unrecognized compensation cost related to share-based compensation	$ 15,000
Weighted-average service period, years	2 years 72 days

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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