Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities
Net income (loss)	$ 75.6	$ (54.7)	$ 11.2
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	231.0	169.6	217.4
Loss on extinguishment of debt	19.6	29.6	13.6
Loss from CyrusOne equity method investment	7.0	10.7	0
Gain on sale of CyrusOne equity method investment	(192.8)	0	0
(Gain) loss on sale of assets	(0.3)	2.4	(1.6)
Impairment of assets	12.1	0	14.2
Provision for loss on receivables	10.4	11.3	13.9
Noncash portion of interest expense	6.2	7.5	7.8
Deferred income taxes expense, including valuation allowance change	47.4	(2.7)	21.6
Pension and other postretirement payments in excess of expense	(25.7)	(49.7)	(28.4)
Amortization of deferred gain	(22.9)	(3.3)	(2.3)
Stock-based compensation	3.3	4.9	5.2
Excess tax benefit for share based payments	(0.1)	(0.5)	(2.4)
Other, net	3.9	(3.4)	0.9
Changes in operating assets and liabilities, net of effects of divestitures:
(Increase) decrease in receivables	(23.7)	0.5	(33.6)
Increase in inventory, materials, supplies, prepaid expenses and other current assets	(7.2)	(0.8)	(14.5)
Increase (decrease) in accounts payable	38.7	(17.7)	(6.9)
Decrease in accrued and other current liabilities	(0.8)	(18.1)	(10.0)
Decrease in other noncurrent assets	0.7	0.8	4.6
(Decrease) increase in other noncurrent liabilities	(7.2)	(7.6)	2.0
Net cash provided by operating activities	175.2	78.8	212.7
Cash flows from investing activities
Capital expenditures	(182.3)	(196.9)	(367.2)
Proceeds from sale of CyrusOne equity method investment	355.9	0	0
Dividends received from CyrusOne	28.4	21.3	0
Proceeds from sale of Wireless spectrum licenses	194.4	0	0
Proceeds from sale of assets	2.0	2.0	1.6
Increase in restricted cash	0	0	(11.1)
Release of restricted cash	0	0.4	4.9
Cash divested from deconsolidation of CyrusOne	0	(12.2)	0
Other, net	(5.8)	0	0
Net cash used in investing activities	392.6	(185.4)	(371.8)
Cash flows from financing activities
Proceeds from issuance of long-term debt	0	536.0	525.0
Net (decrease) increase in corporate credit and receivables facilities with initial maturities less than 90 days	(127.0)	94.2	52.0
Repayment of debt	(376.5)	(530.8)	(442.4)
Debt issuance costs	(0.9)	(6.7)	(20.9)
Dividends paid on preferred stock	(10.4)	(10.4)	(10.4)
CyrusOne stock issuance costs	0	0	(5.7)
Common stock repurchase	0	0	(0.3)
Proceeds from exercise of options and warrants	1.3	7.1	12.1
Excess tax benefit for share based payments	0.1	0.5	2.4
Financing obligations and other, net	(1.1)	(2.3)	(2.8)
Net cash provided by (used in) financing activities	(514.5)	87.6	109.0
Net increase (decrease) in cash and cash equivalents	53.3	(19.0)	(50.1)
Cash and cash equivalents at beginning of year	4.6	23.6	73.7
Cash and cash equivalents at end of year	$ 57.9	$ 4.6	$ 23.6