v3.21.2

Summary of Significant Accounting Policies - Deferred Revenue (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021 USD ($)
Capitalized Contract Cost [Line Items]
Cash received in advance and not recognized as revenue	$ 372.9
Increase from netting of contract assets and liabilities on contract by contract basis	3.2
Increase in revenue recognized from current year invoices	300.4
Revenue recognized that was included in the deferred revenue balance in prior year	66.2
Revenue from remaining performance obligations	$ 1,300.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Capitalized Contract Cost [Line Items]
Remaining performance obligation, percentage	48.00%
Performance obligations expected to be satisfied, expected timing	24 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Capitalized Contract Cost [Line Items]
Remaining performance obligation, percentage	38.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01 | Minimum
Capitalized Contract Cost [Line Items]
Performance obligations expected to be satisfied, expected timing	25 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01 | Maximum
Capitalized Contract Cost [Line Items]
Performance obligations expected to be satisfied, expected timing	48 months

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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