Condensed Consolidated Statements of Shareowners' Deficit Statement - USD ($) shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance, Shareowners' Equity (Deficit)	$ (112.3)	$ (143.4)	$ (75.0)	$ (117.9)
Net loss	(13.6)	(17.7)	(46.0)	(39.8)
Other comprehensive income (loss)	(1.1)	6.8	(3.4)	8.0
Shares issued under employee plans		0.0	0.0	0.0
Shares purchased under employee plans and other		(0.1)	(0.8)	(2.1)
Stock-based compensation	2.0	1.9	5.4	4.5
Dividends on preferred stock	(2.6)	(2.6)	(7.8)	(7.8)
Stock consideration for acquisition of Hawaiian Telcom		121.2		121.2
Ending Balance, Shareowners' Equity (Deficit)	(127.6)	(33.9)	(127.6)	(33.9)
Preferred Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance, Shareowners' Equity (Deficit)	$ 129.4	$ 129.4	$ 129.4	$ 129.4
Beginning Balance, Shares	3.1	3.1	3.1	3.1
Ending Balance, Shareowners' Equity (Deficit)	$ 129.4	$ 129.4	$ 129.4	$ 129.4
Ending Balance, Shares	3.1	3.1	3.1	3.1
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance, Shareowners' Equity (Deficit)	$ 0.5	$ 0.4	$ 0.5	$ 0.4
Beginning Balance, Shares	50.4	42.4	50.2	42.2
Shares issued under employee plans		$ 0.0	$ 0.0	$ 0.0
Shares issued under employee plans		0.1	0.2	0.3
Stock consideration for acquisition of Hawaiian Telcom		$ 0.1		$ 0.1
Stock consideration for acquisition of Hawaiian Telcom, Shares		7.7		7.7
Ending Balance, Shareowners' Equity (Deficit)	$ 0.5	$ 0.5	$ 0.5	$ 0.5
Ending Balance, Shares	50.4	50.2	50.4	50.2
Additional Paid-in Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance, Shareowners' Equity (Deficit)	$ 2,677.4	$ 2,561.0	$ 2,680.0	$ 2,565.6
Shares issued under employee plans		0.0	0.0	0.0
Shares purchased under employee plans and other		(0.1)	(0.8)	(2.1)
Stock-based compensation	2.0	1.9	5.4	4.5
Dividends on preferred stock	(2.6)	(2.6)	(7.8)	(7.8)
Stock consideration for acquisition of Hawaiian Telcom		121.1		121.1
Ending Balance, Shareowners' Equity (Deficit)	2,676.8	2,681.3	2,676.8	2,681.3
Retained Earnings [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance, Shareowners' Equity (Deficit)	(2,741.8)	(2,661.7)	(2,709.4)	(2,639.6)
Net loss	(13.6)	(17.7)	(46.0)	(39.8)
Ending Balance, Shareowners' Equity (Deficit)	(2,755.4)	(2,679.4)	(2,755.4)	(2,679.4)
AOCI Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance, Shareowners' Equity (Deficit)	(177.8)	(172.5)	(175.5)	(173.7)
Other comprehensive income (loss)	(1.1)	6.8	(3.4)	8.0
Ending Balance, Shareowners' Equity (Deficit)	$ (178.9)	$ (165.7)	$ (178.9)	$ (165.7)

Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.

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