Share-Based Compensation Expense (Schedule of Share-Based Compensation Expense Showing Amount Attributable to Each Category) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share Based Compensation [Abstract]
Amortization of restricted stock awards and restricted stock unit awards	$ 2,640	$ 2,774
Amortization of stock option awards	21	34
Discount given on employee stock purchase transactions through our Employee Stock Purchase Plan	108	107
Share-based compensation expense from continuing operations	2,769	2,915
Share-based compensation expense from discontinued operations		462
Total share-based compensation expense	$ 2,769	$ 3,377

Allocated share based compensation expense (benefit) from discontinued operations.

No definition available.

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- Definition

Allocated share based compensation expense from continuing operations.

+ References

No definition available.

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- Definition

Share-based compensation discount to employees on ESPP.

+ References

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- References

No definition available.

+ Details

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ References

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