Business and Summary of Significant Accounting Principles (Rural Health Care (RHC) Program) (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
USAC
Public Utilities, General Disclosures [Line Items]
Reduction in revenues	$ 5.5

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.

No definition available.

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