Payments for restructuring and severance

No definition available.

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Namespace Prefix:	cbb_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Restructuring and severance related charges (reversals)

+ References

No definition available.

+ Details

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Namespace Prefix:	cbb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(2))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

+ Details

Name:	us-gaap_RestructuringReserveNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

Name:	us-gaap_RestructuringReserveRollForward
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=us-gaap_EmployeeSeveranceMember
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- Details

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- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=us-gaap_OtherRestructuringMember
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Restructuring and Severance Charges (Details) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Reserve [Roll Forward]
Beginning balance	$ 11.2				$ 4.9	$ 1.1	$ 4.9	$ 14.3
Restructuring and severance related charges (reversals)		$ 11.9	$ 0.3	$ 2.3	3.4	11.9	6.0	(0.4)
Utilizations						(1.8)	(9.8)	(9.0)
Ending balance		11.2				11.2	1.1	4.9
Restructuring liabilities included in other current liabilities		7.4				7.4	0.9
Restructuring liabilities included in other noncurrent liabilities		3.8				3.8	0.2
Entertainment and Communications [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	7.5				3.9	0.8	3.9	10.5
Restructuring and severance related charges (reversals)						7.7	1.6	(0.5)
Utilizations						(1.0)	(4.7)	(6.1)
Ending balance		7.5				7.5	0.8	3.9
IT Services and Hardware [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	3.0				0.3	0.3	0.3	0.8
Restructuring and severance related charges (reversals)						3.3	2.8	0.0
Utilizations						(0.6)	(2.8)	(0.5)
Ending balance		3.0				3.0	0.3	0.3
Corporate Segment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.7				0.7	0.0	0.7	3.0
Restructuring and severance related charges (reversals)						0.9	1.6	0.1
Utilizations						(0.2)	(2.3)	(2.4)
Ending balance		0.7				0.7	0.0	0.7
Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	11.0				3.0	0.2	3.0	8.4
Restructuring and severance related charges (reversals)	25.0					12.5	3.3	1.0
Utilizations						(1.7)	(6.1)	(6.4)
Ending balance		11.0				11.0	0.2	3.0
Lease Abandonment [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.2				1.8	0.8	1.8	5.8
Restructuring and severance related charges (reversals)						(0.5)	0.3	(1.4)
Utilizations						(0.1)	(1.3)	(2.6)
Ending balance		0.2				0.2	0.8	1.8
Contract Terminations [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	$ 0.0				$ 0.1	0.1	0.1	0.1
Restructuring and severance related charges (reversals)						(0.1)	2.4	0.0
Utilizations						0.0	(2.4)	0.0
Ending balance		$ 0.0				$ 0.0	$ 0.1	$ 0.1