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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized tax benefit, including interest and penalties	$ 18,016
Unrecognized tax benefits that would affect effective tax rate	15,761
Amount of uncertain tax liability expected to be paid within one year	6,546
Amount of uncertain tax liability included in Other long-term liabilities	11,470
Unrecognized tax benefits related to lapse of statute of limitations, previously unrecognized	3,033
Liabilities for tax-related interest and penalties	2,105	$ 1,962	$ 1,289
Settlement and Lapse of Statute
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized tax benefits expected to be recognized within the next 12 months	$ 6,546

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- Definition

Unrecognized Tax Benefit, Including Interest And Penalties

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- Definition

The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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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Amount recognized for uncertainty in income taxes classified as current.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount recognized for uncertainty in income taxes classified as noncurrent.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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