Description of Business (Proposed Merger) (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Business Acquisition [Line Items]
Proposed merger, agreement termination fee | $	$ 11.9
Professional fees | $	$ 2.4
Contingent consideration, cash
Business Acquisition [Line Items]
Proposed merger, company shareholders' consideration in cash (per share) | $ / shares	$ 30.75
Proposed merger, consideration proration of final distribution (as a percentage)	60.00%
Contingent consideration, Cincinnati Bell common stock
Business Acquisition [Line Items]
Proposed merger, company shareholders' consideration in Cincinnati Bell common stock shares | shares	1.6305
Proposed merger, consideration proration of final distribution (as a percentage)	40.00%
Contingent consideration, cash and Cincinnati Bell common stock mixture
Business Acquisition [Line Items]
Proposed merger, company shareholders' consideration in cash (per share) | $ / shares	$ 18.45
Proposed merger, company shareholders' consideration in Cincinnati Bell common stock shares | shares	0.6522