Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net income (loss)	$ 353.7	$ 75.6	$ (54.7)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	170.2	231.0	169.6
Loss on extinguishment of debt	20.9	19.6	29.6
Loss from CyrusOne investment	5.1	7.0	10.7
Gain on sale of CyrusOne investment	(449.2)	(192.8)	0.0
Loss (gain) on sale of assets	0.4	(0.3)	2.4
Impairment of assets	0.0	12.1	0.0
Provision for loss on receivables	8.5	10.4	11.3
Noncash portion of interest expense	4.6	6.2	7.5
Deferred income tax expense (benefit), including valuation allowance change	184.5	47.4	(2.7)
Pension and other postretirement payments in excess of expense	(11.5)	(25.7)	(49.7)
Deferred gain on sale of wireless spectrum licenses - discontinued operations	(112.6)	0.0	0.0
Amortization of deferred gain - discontinued operations	(6.5)	(22.9)	(3.3)
Stock-based compensation	4.1	3.3	4.9
Excess tax benefit for share based payments	(0.1)	(0.1)	(0.5)
Gain on transfer of lease obligations - discontinued operations	(15.9)	0.0	0.0
Other, net	(2.3)	3.9	(3.4)
Changes in operating assets and liabilities, net of effects of divestitures:
(Increase) decrease in receivables	(1.9)	(23.7)	0.5
Decrease (increase) in inventory, materials, supplies, prepaid expenses and other current assets	3.6	(7.2)	(0.8)
(Decrease) increase in accounts payable	(17.0)	38.7	(17.7)
Decrease in accrued and other current liabilities	(30.6)	(0.8)	(18.1)
Decrease in other noncurrent assets	1.5	0.7	0.8
Increase (decrease) in other noncurrent liabilities	1.4	(7.2)	(7.6)
Net cash provided by operating activities	110.9	175.2	78.8
Cash flows from investing activities
Capital expenditures	(283.6)	(182.3)	(196.9)
Proceeds from sale of CyrusOne investment	643.9	355.9	0.0
Dividends received from CyrusOne	22.2	28.4	21.3
Proceeds from sale of wireless spectrum licenses	0.0	194.4	0.0
Proceeds from sale of assets	1.0	2.0	2.0
Release of restricted cash	0.0	0.0	0.4
Cash divested from deconsolidation of CyrusOne	0.0	0.0	(12.2)
Other, net	(0.3)	(5.8)	0.0
Net cash provided by (used in) investing activities	383.2	392.6	(185.4)
Cash flows from financing activities
Proceeds from issuance of long-term debt	0.0	0.0	536.0
Net (decrease) increase in corporate credit and receivables facilities with initial maturities less than 90 days	(1.6)	(127.0)	94.2
Repayment of debt	(531.7)	(376.5)	(530.8)
Debt issuance costs	(0.4)	(0.9)	(6.7)
Dividends paid on preferred stock	(10.4)	(10.4)	(10.4)
Proceeds from exercise of options and warrants	0.0	1.3	7.1
Excess tax benefit for share based payments	0.1	0.1	0.5
Other, net	(0.6)	(1.1)	(2.3)
Net cash (used in) provided by financing activities	(544.6)	(514.5)	87.6
Net (decrease) increase in cash and cash equivalents	(50.5)	53.3	(19.0)
Cash and cash equivalents at beginning of year	57.9	4.6	23.6
Cash and cash equivalents at end of year	$ 7.4	$ 57.9	$ 4.6