Name:	cas_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsSubsequentGrantsWeightedAverageGrantDateFairValue
Namespace Prefix:	cas_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The weighted average fair value at grant date for performance based awards issued subsequent to period end.

No definition available.

Name:	cas_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceSharesGrantDateFairValue
Namespace Prefix:	cas_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Number of performance share awards granted under the active LTCP's to the President and CEO appointed subsequent to period end.

No definition available.

Name:	cas_ShareBasedCompensationArrangementsShareBasedPaymentAwardsGrantedPerformanceShares
Namespace Prefix:	cas_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Number of performance share awards granted under the active LTCP's to the President and CEO appointed subsequent to period end, which contain a market-based performance condition.

No definition available.

Name:	cas_ShareBasedCompensationArrangementsShareBasedPaymentAwardsGrantedPerformanceSharesMarketCondition
Namespace Prefix:	cas_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Number of restricted stock units granted to the President and CEO appointed subsequent to the end of the period.

No definition available.

Name:	cas_ShareBasedCompensationArrangementsShareBasedPaymentAwardsGrantedRestrictedStockUnits
Namespace Prefix:	cas_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Subsequent event president and chief executive officer base salary.

No definition available.

Name:	cas_SubsequentEventPresidentAndChiefExecutiveOfficerBaseSalary
Namespace Prefix:	cas_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Subsequent event president and chief executive officer one time cash signing bonus.

No definition available.

Name:	cas_SubsequentEventPresidentAndChiefExecutiveOfficerOneTimeCashSigningBonus
Namespace Prefix:	cas_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Time period over which restricted stock units received by President and CEO in connection with appointment, will vest, assuming continued employment.

No definition available.

Name:	cas_SubsequentEventPresidentAndChiefExecutiveOfficerRequisiteServicePeriod
Namespace Prefix:	cas_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Subsequent event president and chief executive officer target LTCP incentive opportunity as a percentage of base salary.

No definition available.

Name:	cas_SubsequentEventPresidentAndChiefExecutiveOfficerTargetLtcpPercentage
Namespace Prefix:	cas_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Subsequent event president and chief executive officer target STIP payout as a percentage of base salary.

No definition available.

Name:	cas_SubsequentEventPresidentAndChiefExecutiveOfficerTargetStipPercentage
Namespace Prefix:	cas_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	cas_SubsequentEventsTextualAbstract
Namespace Prefix:	cas_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.