Debt Covenant, Outstanding Borrowing Balance Threshold, That Require Minimum Levels Of EBITDA

No definition available.

Name:	cbk_DebtCovenantOutstandingBorrowingBalanceThresholdThatRequireMinimumLevelsOfEBITDA
Namespace Prefix:	cbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount of borrowing availability under the covenant terms of the credit facility.

+ References

No definition available.

+ Details

Name:	cbk_DebtInstrumentCovenantBorrowingAvailabilityRequirementAmount
Namespace Prefix:	cbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt Instrument, Covenant Borrowing Availability Requirement, As Percentage Of Borrowing Base

+ References

No definition available.

+ Details

Name:	cbk_DebtInstrumentCovenantBorrowingAvailabilityRequirementAsPercentageOfBorrowingBase
Namespace Prefix:	cbk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

Name:	us-gaap_ExtinguishmentOfDebtAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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://fasb.org/us-gaap/role/ref/legacyRef
-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

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=cbk_WellsFargoBankN.A.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

Subsequent Events (Details) - Revolving Credit Facility - Wells Fargo Bank, N.A. - USD ($)			12 Months Ended
	Feb. 27, 2020	Aug. 03, 2018	Feb. 01, 2020
Subsequent Event [Line Items]
Maximum availability under credit facility		$ 50,000,000.0
Borrowing base to maintain, percentage		10.00%	10.00%
Borrowing base to maintain		$ 3,000,000.0	$ 3,000,000.0
First In Last Out Credit Facility
Subsequent Event [Line Items]
Maximum availability under credit facility		$ 5,000,000.0
First In Last Out Credit Facility \| Subsequent Event
Subsequent Event [Line Items]
Debt eliminated	$ 5,000,000
Term Loan Facility \| Subsequent Event
Subsequent Event [Line Items]
Maximum availability under credit facility	$ 10,000,000
Interest rate	10.00%
Term of credit facility	5 years
Borrowing base to maintain, percentage	10.00%
Borrowing base to maintain	$ 3,000,000
Debt covenant, outstanding borrowing balance threshold, that require minimum levels of EBITDA	$ 5,000,000