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Income Taxes (Narrative) (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
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Income Tax Contingency [Line Items] |  |
Gross liability for unrecognized tax benefits, exclusive of interest and penalties | $ 16,721 | $ 15,911
Unrecognized tax benefits that would affect effective tax rate | 16,532 | 15,761
Interest and penalties on unrecognized benefits | 1,835 | $ 2,105
Settlement and Lapse of Statute |  |
Income Tax Contingency [Line Items] |  |
Unrecognized tax benefits within the next twelve months | $ 4,497 |

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319 + Details
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