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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Gross liability for unrecognized tax benefits, exclusive of interest and penalties	$ 14,685	$ 14,480
Unrecognized tax benefits that would affect effective tax rate	13,986	13,737
Interest and penalties on unrecognized benefits	1,218	$ 1,175
Estimated one-time transition tax	11,544
Estimated one-time transition tax, current	915
Estimated one-time transition tax, noncurrent	10,629
Settlement and Lapse of Statute [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefits within the next twelve months	$ 2,944

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
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