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Income Taxes (Unrecognized Tax Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 14,480	$ 17,287	$ 14,517
Tax positions related to current year:
Gross additions	2,446	3,180	3,756
Tax positions related to prior years:
Gross additions	340	211	1,762
Settlements	(278)	(352)	(378)
Lapses on statute of limitations	(2,621)	(5,846)	(2,370)
Ending balance	$ 14,367	$ 14,480	$ 17,287

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- Definition

Unrecognized Tax Benefits, Tax Positions Related To Current Year [Abstract]

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Unrecognized Tax Benefits, Tax Positions Related To Prior Years [Abstract]

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of unrecognized tax benefits.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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-Name Accounting Standards Codification
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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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