Basis Of Presentation And New Accounting Standards - New Accounting Standards (Details) - USD ($) $ in Thousands		9 Months Ended
Jan. 01, 2020	Sep. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Provision for expected credit losses on accounts receivable		$ 2,387
Retained Earnings \| Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Provision for expected credit losses on accounts receivable	$ 600
Tax effect of expected credit losses	$ 200

Amount of expense (reversal of expense) for expected credit loss on right to consideration in exchange for good or service transferred to customer when right to consideration is unconditional.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 45
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 50
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-Publisher FASB
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