XML 26 R104.htm IDEA: XBRL DOCUMENT v2.4.1.9

Off-Balance Sheet Activities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Unused lines of Credit - Fixed Rate [Member]
Contractual amount of financial instruments with off-balance sheet risk	7,076us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = us-gaap_UnusedLinesOfCreditMember	$ 3,495us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = us-gaap_UnusedLinesOfCreditMember
Unused lines of Credit - Variable Rate [Member]
Contractual amount of financial instruments with off-balance sheet risk	60,476us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = cofs_UnusedLinesOfCredit1Member	66,421us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = cofs_UnusedLinesOfCredit1Member
Commitments to fund loans - Fixed Rate [Member]
Contractual amount of financial instruments with off-balance sheet risk	3,116us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = us-gaap_CommitmentsToExtendCreditMember	7,464us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = us-gaap_CommitmentsToExtendCreditMember
Commitments to fund loans - Variable Rate [Member]
Contractual amount of financial instruments with off-balance sheet risk	1,050us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = cofs_CommitmentsToExtendCredit1Member	$ 1,899us-gaap_FairValueDisclosureOffbalanceSheetRisksAmountAsset / us-gaap_FinancialInstrumentAxis = cofs_CommitmentsToExtendCredit1Member
Lower Range [Member]
Interest rate of commitments	3.75%cofs_InterestRateCommitmentsToExtendCredit / us-gaap_RangeAxis = us-gaap_MinimumMember
Term of commitments	18 months
Upper Range [Member]
Interest rate of commitments	8.20%cofs_InterestRateCommitmentsToExtendCredit / us-gaap_RangeAxis = us-gaap_MaximumMember
Term of commitments	30 years

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- Definition

The interest rate for commitments to extend credit.

+ References

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- Definition

The maturity term of commitments to extend credit.

+ References

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- Definition

The fair value of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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