Commitments And Contingencies (Narrative) (Details) $ in Millions	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Contract Termination
Loss Contingencies
Receivables	$ 42.7	$ 42.3
Receivables, long-term	$ 7.8
Weighted Average Cost of Capital
Loss Contingencies
Weighted average cost of capital	0.130

Value of input used to measure contingent consideration liability from business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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+ References

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Carrying amounts due as of the balance sheet date of the sum of amounts receivable other than from customers.

+ References

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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The noncurrent portion of the receivable other than from customers, that is amounts expected to be collected after one year or the normal operating cycle, if longer.

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