Document and Entity Information Document	6 Months Ended
	Jun. 30, 2019 $ / shares	Jul. 31, 2019 shares	Dec. 31, 2018 $ / shares
Class of Stock [Line Items]
Entity Registrant Name	CINCINNATI BELL INC.
Entity Central Index Key	0000716133
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Small Business	false
Document Type	10-Q
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding | shares		50,420,449
Fractional Interest in Cumulative Convertible Preferred Stock, Depositary Shares	0.05
Common Stock, Par or Stated Value Per Share | $ / shares	$ 0.01		$ 0.01
Entity File Number	1-8519
Entity Tax Identification Number	31-1056105
Entity Address, Address Line One	221 East Fourth Street
Entity Address, City or Town	Cincinnati
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	45202
City Area Code	513
Local Phone Number	397-9900
Entity Incorporation, State or Country Code	OH
Document Quarterly Report	true
Document Transition Report	false
Common Stock [Member]
Class of Stock [Line Items]
Trading Symbol	CBB
Security Exchange Name	NYSE
Title of 12(b) Security	Common Shares
Preferred Stock [Member]
Class of Stock [Line Items]
Trading Symbol	CBB.PB
Security Exchange Name	NYSE
Title of 12(b) Security	Convertible Preferred Stock