v3.10.0.1

Revenue Recognition and Related Costs (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018	Jan. 01, 2018
Revenue from Contract with Customer [Abstract]
Trade receivables, allowance for doubtful accounts	$ 57.0	$ 57.0	$ 89.5
Contract assets	27.7	27.7	26.1
Deferred revenue	889.2	889.2	1,005.2
Revenue recognized		801.8
Aggregate assets associated with incremental costs to obtain a contract and contract fulfillment costs	68.4	68.4	$ 68.1
Amortization related to contract costs	$ 28.5	$ 51.3
Residential Service
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unsatisfied performance obligations term	12 months	12 months
Mobile Contracts | Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unsatisfied performance obligations term	1 year	1 year
Mobile Contracts | Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unsatisfied performance obligations term	3 years	3 years
Total B2B revenue | Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unsatisfied performance obligations term	1 year	1 year
Total B2B revenue | Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unsatisfied performance obligations term	5 years	5 years

X

- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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- Definition

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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