Name:	clst_CommitmentsToExtendCredit
Namespace Prefix:	clst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of financial instruments with off-balance-sheet risk.

No definition available.

Name:	clst_FinancialInstrumentsOffBalanceSheetRisk
Namespace Prefix:	clst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amounts of unused overdraft privilege at the end of reporting period.

No definition available.

Name:	clst_OverdraftPrivilegeUnusedAmounts
Namespace Prefix:	clst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount of unfunded financial commitments as at the end of the reporting period.

No definition available.

Name:	clst_UnfundedConstructionLoansInProcess
Namespace Prefix:	clst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.