Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2014

Commitments and Contingencies [Abstract]

Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]

At December 31, 2014, future minimum lease payments required under operating leases having initial or remaining non-cancellable lease terms for the next five years are as follows:

(dollars in millions)
2015	$	10.3
2016	6.5
2017	5.1
2018	3.7
2019	3.2
Thereafter	21.6
Total	$	50.4

Schedule of Change in Asset Retirement Obligation [Table Text Block]

The following table presents the activity for the Company’s asset retirement obligations, which are included in "Other noncurrent liabilities" in the Consolidated Balance Sheets:

	December 31,
(dollars in millions)	2014			2013
Balance, beginning of period	$	8.5		$	7.1
Liabilities settled	(0.2		)	(0.1		)
Liabilities incurred	—			0.1
Revisions to estimated cash flow	0.3			1.1
Accretion expense	0.5			0.5
Deconsolidation of CyrusOne	—			(0.2		)
Balance, end of period	$	9.1		$	8.5