Class of Warrant or Right, Percentage of Common Stock Outstanding

No definition available.

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Period Type:	instant

- Definition

Debt Exchange, Amount Exchanged

+ References

No definition available.

+ Details

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Namespace Prefix:	cvo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Exchange, Percentage Exchanged

+ References

No definition available.

+ Details

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Namespace Prefix:	cvo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

Name:	us-gaap_UnamortizedDebtIssuanceExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=cvo_SeniorUnsecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cvo_A115SeniorNotesDue2017Member
Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=cvo_A6.000SeniorUnsecuredNotesDue2024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	cvo_DebtTransactionsAxis=cvo_ExchangeOfferMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	cvo_DebtTransactionsAxis=cvo_AffiliateExchangeAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=cvo_AffiliateNoteholdersMember
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Long-Term Debt (Exchange Offer) (Details) - USD ($) $ / shares in Units, $ in Millions	Jul. 02, 2016	Jun. 10, 2016	Jan. 02, 2016
Debt Instrument [Line Items]
Fair value of long-term debt	$ 885.4		$ 895.7
Senior unsecured debt [Member] \| 11.5% senior notes due 2017 [Member]
Debt Instrument [Line Items]
Long-term debt, outstanding principal amount	40.5		199.7
Senior unsecured debt [Member] \| 6.000% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt, outstanding principal amount	104.5		$ 0.0
Exchange Offer [Member] \| Senior unsecured debt [Member] \| 11.5% senior notes due 2017 [Member]
Debt Instrument [Line Items]
Debt exchange, amount exchanged		$ 149.3
Debt exchanged, percentage exchanged (percent)		80.00%
Long-term debt, outstanding principal amount	40.5
Exchange Offer [Member] \| Senior unsecured debt [Member] \| 6.000% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt, outstanding principal amount		$ 104.5
Warrants, percentage of common stock outstanding (percent)		16.60%
Unamortized debt issuance costs	$ 7.3	$ 7.4
Fair value of long-term debt		92.0
Unamortized original issuance discount		$ 12.5
Warrant, number of shares per warrant (shares)		0.125
Warrant, exercise price (dollar per share)		$ 12.00
Warrants, fair value		$ 6.3
Affiliate Exchange Agreement [Member] \| Affiliate noteholders [Member] \| Senior unsecured debt [Member] \| 11.5% senior notes due 2017 [Member]
Debt Instrument [Line Items]
Long-term debt, outstanding principal amount		$ 4.2