Debt, Amount of Outstanding Senior Secured Debt Triggering a Springing Maturity

No definition available.

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

- Definition

Line of Credit Facility, Additional Borrowing Capacity

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Borrowing Capacity, Reduction

+ References

No definition available.

+ Details

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

- Definition

Maximum contractual interest rate for funds borrowed, under the debt agreement.

+ 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

+ 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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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 fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

Name:	us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=cvo_RevolvingCreditFacilityDue2014Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cvo_ABLRevolvingCreditFacilityDue2021Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=cvo_A2013CreditFacilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cvo_Termloanfacilitydue2017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

Long-Term Debt (ABL Facility) (Details) - USD ($)	Dec. 11, 2013	Apr. 16, 2013	Dec. 31, 2016	Jun. 10, 2016	Jan. 02, 2016	Jan. 30, 2015
Debt Instrument [Line Items]
Unamortized debt issuance costs			$ 18,100,000		$ 16,500,000
Asset based lending facility [Member] \| Revolving credit facility due 2014 [Member]
Debt Instrument [Line Items]
Credit facility, borrowing capacity		$ 170,000,000
Asset based lending facility [Member] \| ABL Facility due 2021 [Member]
Debt Instrument [Line Items]
Credit facility, borrowing capacity		200,000,000				$ 240,000,000
Unamortized debt issuance costs	$ 300,000		$ 3,600,000		$ 2,400,000	1,300,000
Additional borrowing capacity	30,000,000					$ 10,000,000
Long-term debt [Member] \| 2013 Credit Facilities [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs		$ 7,200,000
Long-term debt [Member] \| Term loan facility due 2017 [Member]
Debt Instrument [Line Items]
Repayments of debt	$ 28,200,000
Minimum [Member] \| Asset based lending facility [Member] \| ABL Facility due 2021 [Member]
Debt Instrument [Line Items]
Commitment fee percentage (percent)		0.375%
Maximum [Member] \| Asset based lending facility [Member] \| ABL Facility due 2021 [Member]
Debt Instrument [Line Items]
Commitment fee percentage (percent)		0.50%
LIBOR [Member] \| Asset based lending facility [Member] \| ABL Facility due 2021 [Member]
Debt Instrument [Line Items]
Debt, interest rate, minimum (percent)		2.00%
Debt, interest rate, maximum (percent)		2.50%
Prime Rate [Member] \| Asset based lending facility [Member] \| ABL Facility due 2021 [Member]
Debt Instrument [Line Items]
Debt, interest rate, minimum (percent)		1.00%
Debt, interest rate, maximum (percent)		1.50%
ABL amendment [Member] \| Asset based lending facility [Member] \| ABL Facility due 2021 [Member]
Debt Instrument [Line Items]
Credit facility, borrowing capacity				$ 190,000,000
Unamortized debt issuance costs				2,300,000
Credit facility, decrease in borrowing capacity				50,000,000
Amount of outstanding senior secured debt triggering a springing maturity				$ 10,000,000