Business and Summary of Significant Accounting Principles (Wireless Acquisition Narrative) (Details) - USD ($) $ in Millions		12 Months Ended
	Feb. 02, 2015	Dec. 31, 2016	Dec. 31, 2015
Noncontrolling Interest [Line Items]
Payments to acquire assets and interest	$ 293.2
Other Income (Expense)
Noncontrolling Interest [Line Items]
Gain from adjustment to fair value		$ 3.1
Other Income (Expense) | Rights to Receive Future Capacity
Noncontrolling Interest [Line Items]
Gain from adjustment to fair value	$ 1.2
Other Income (Expense) | Rights to Use Capacity
Noncontrolling Interest [Line Items]
Impairment of intangible assets			$ 3.8