Represents the period over which the matching contributions vest under the defined contribution plan.

No definition available.

Name:	cvi_DefinedContributionPlanMatchingContributionVestingPeriod
Namespace Prefix:	cvi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of defined-contribution 401(k) plans.

+ References

No definition available.

+ Details

Name:	cvi_DefinedContributionPlansNumber
Namespace Prefix:	cvi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

Name:	us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_DefinedContributionPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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

- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_RetirementPlanNameAxis=cvi_UnionPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Benefit Plans (Details) $ in Millions	8 Months Ended	12 Months Ended
Benefit Plans (Details) $ in Millions	Dec. 31, 2017 USD ($) plan	Dec. 31, 2017 USD ($) plan	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Defined Contribution Plan Disclosure [Line Items]
Number of defined-contribution 401(k) plans \| plan	2	2
Percentage of employer match		100.00%
Percent of employees' gross pay matched		6.00%
Vesting schedule for employer's matching funds		3 years
Matching contributions made by the company		$ 8.5	$ 8.1	$ 7.3
Union Plan
Defined Contribution Plan Disclosure [Line Items]
Matching contributions made by the company	$ 0.0