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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Gross liability for unrecognized tax benefits, exclusive of interest and penalties	$ 16,038	$ 17,287
Unrecognized tax benefits that would affect effective tax rate	13,386	14,868
Interest and penalties on unrecognized benefits	1,361	$ 1,224
Settlement and Lapse of Statute [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefits within the next twelve months	$ 2,648

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- Definition

Gross Liability For Unrecognized Tax Benefits Exclusive Of Interest And Penalties

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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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- Definition

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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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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- Definition

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

+ References

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)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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