Represents the weighted average ancillary income per year, used as an input to measure fair value.

No definition available.

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Namespace Prefix:	chfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the weighted average cost to service per year, used as an input to measure fair value.

+ References

No definition available.

+ Details

Name:	chfc_FairValueInputsWeightedAverageCostToServicePerYear
Namespace Prefix:	chfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the weighted average float rate, used as an input to measure fair value.

+ References

No definition available.

+ Details

Name:	chfc_FairValueInputsWeightedAverageFloatRate
Namespace Prefix:	chfc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of revenue from servicing real estate mortgages, credit cards, and other financial assets held by others.

+ References

No definition available.

+ Details

Name:	chfc_ServicingFeesNetExcludingPremiums
Namespace Prefix:	chfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueInputsDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

+ Details

Name:	us-gaap_FairValueInputsPrepaymentRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_WeightedAverageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByAssetClassAxis=chfc_MortgageLoanServicingRightsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Loan Servicing Rights (Assumptions Used in Determining Fair Value) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Transfers and Servicing [Abstract]
Loan servicing fee income	$ 8,700,000	$ 5,400,000	$ 2,900,000
Commercial Real Estate
Loan servicing rights
WA float range (as a percent)	0.53%
Commercial Real Estate \| Minimum
Loan servicing rights
Prepayment speed (as a percent)	0.00%
Cost to service/per year	$ 467
Commercial Real Estate \| Maximum
Loan servicing rights
Prepayment speed (as a percent)	22.47%
Cost to service/per year	$ 500
Commercial Real Estate \| Weighted Average
Loan servicing rights
Discount rate (as a percent)	16.46%
Mortgage
Loan servicing rights
WA Ancillary income/per year	$ 28	$ 20
WA float range (as a percent)	1.01%	1.72%
Mortgage \| Minimum
Loan servicing rights
Prepayment speed (as a percent)	0.00%	6.96%
Cost to service/per year	$ 65	$ 70
Mortgage \| Maximum
Loan servicing rights
Prepayment speed (as a percent)	99.75%	17.65%
Cost to service/per year	$ 90	$ 85
Mortgage \| Weighted Average
Loan servicing rights
Discount rate (as a percent)	10.09%	10.04%