Revenue from Contracts with Customers Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Entities	Sep. 30, 2019 USD ($)
Revenue from Contract with Customers [Line Items]
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	$ 4.3	$ 5.9	$ 9.4	$ 9.0
Number of Reportable Segments \| Entities			1
Contract Receivable, Due after Next Rolling Twelve Months	1.7		$ 1.7
Contract with Customer, Liability, Revenue Recognized	3.8		22.3
Revenue, Remaining Performance Obligation, Amount	$ 2,400.0		$ 2,400.0
UNITED STATES \| Revenue from Contract with Customer, Segment Benchmark [Member]
Revenue from Contract with Customers [Line Items]
Concentration Risk, Percentage	99.00%	99.00%	99.00%	99.00%

[Line Items] for Revenue from Contract with Customers [Table]

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of right to consideration in exchange for good or service transferred to customer under long-term contract or program when right to consideration is unconditional, excluding amount withheld under retainage provision in contract, to be collected after next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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