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

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-Publisher FASB
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-Topic 340
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-Section 50
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Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
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-Section 50
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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
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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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Operating Revenues - Contract Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Amortization period of contracts costs	10 years		10 years
Capitalized Contract Cost, Amortization	$ 3.3	$ 3.5	$ 6.4	$ 6.9
Prepaid expenses and other current assets
Disaggregation of Revenue [Line Items]
Long term deferred costs	9.2		9.2		$ 9.7
Other assets
Disaggregation of Revenue [Line Items]
Long term deferred costs	$ 20.7		$ 20.7		$ 20.8