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The amortization period of ESOP contributions made.

No definition available.

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The attained age of the participant to be eligible for the employee stock ownership plan.

No definition available.

Name:	clst_EmployeeStockOwnershipPlanEsopEligibleParticipantAttainedAge
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Data Type:	xbrli:integerItemType
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Number of unallocated shares under the Employee Stock Ownership Plan.

No definition available.

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Data Type:	xbrli:sharesItemType
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Threshold hours that should have been worked by an employee to be considered an eligible participant under the ESOP.

No definition available.

Name:	clst_EmployeeStockOwnershipPlanEsopThresholdHoursToBeWorkedInFirstHalfYearToBeEligibleParticipant
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Data Type:	xbrli:integerItemType
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Number of shares allocated under the Employee Stock Ownership Plan.

No definition available.

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- References

No definition available.

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Amount of cost for defined contribution plan.

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

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

No definition available.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

No definition available.

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The amount of plan compensation cost recognized during the period.

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-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
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The amount reported as a liability as of the balance sheet date by the entity (the employer) of the loan made by a third-party lender to the employer relating to loans made by the employer to the ESOP.

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Fair value of unearned shares held by the employee stock ownership plan (ESOP).

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Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value of unearned shares for all classes of common stock and nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by an employee stock ownership plan (ESOP). Includes the sale of shares or the issuance treasury shares to an ESOP.

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