Long-Term Debt - ABL Credit Facility (Details) - Line of Credit - ABL Credit Facility - USD ($)	Sep. 30, 2016	Dec. 31, 2017
Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument face amount	$ 50,000,000
Available increase in borrowing limit	$ 25,000,000
Sub-limit percentage of total facility	10.00%
Debt issuance costs	$ 1,200,000
Aggregate availability		$ 43,800,000
Debt outstanding		$ 0
Revolving Credit Facility \| LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.00%
Revolving Credit Facility \| Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Step-down rate	0.50%
Swingline Loan
Line of Credit Facility [Line Items]
Debt instrument face amount	$ 5,000,000
Letter of Credit
Line of Credit Facility [Line Items]
Debt instrument face amount	$ 10,000,000

Debt Instrument, Available Increase in Borrowing Limit

No definition available.

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

- Definition

Debt Instrument, Basis Spread on Variable Rate, Step-down

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Sub-limit, Percent of Total Facility

+ References

No definition available.

+ Details

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Namespace Prefix:	cvi_
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Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: 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=64930739&loc=d3e28878-108400

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-Topic 835
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-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the 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))
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+ Details

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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

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Balance Type:	na
Period Type:	duration

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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