Supplemental Cash Flow Information (Tables)

12 Months Ended

Dec. 31, 2018

Supplemental Cash Flow Information [Abstract]

Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]

	Year Ended December 31,
(dollars in millions)	2018			2017			2016
Capitalized interest expense	$	1.0		$	0.7		$	0.7
Cash paid/(received) for:
Interest	131.7			65.7			71.1
Income taxes, net of refunds	(13.8		)	(12.9		)	1.7
Noncash investing and financing activities:
Stock consideration for acquisition of Hawaiian Telcom	121.2			—			—
Accrual of CyrusOne dividends	—			—			1.1
Acquisition of property by assuming debt and other financing arrangements	51.5			17.3			12.0
Acquisition of property on account	35.8			12.0			23.8