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

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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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

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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

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- 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=66048111&loc=d3e19207-110258

+ Details

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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

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- Details

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- Details

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- Details

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Namespace Prefix:
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Loan Servicing Rights (Assumptions Used in Determining Fair Value) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Transfers and Servicing [Abstract]
Loan servicing fee income	$ 18,200,000	$ 8,700,000	$ 5,400,000
Mortgage
Loan servicing rights
Cost to service/per year		66
WA Ancillary income/per year	$ 31	$ 28
WA float range (as a percent)	1.60%	1.00%
Mortgage \| Minimum
Loan servicing rights
Prepayment speed (as a percent)		0.00%	0.00%
Cost to service/per year			$ 65
Mortgage \| Maximum
Loan servicing rights
Prepayment speed (as a percent)		38.80%	99.80%
Cost to service/per year			$ 90
Mortgage \| Weighted Average
Loan servicing rights
Discount rate (as a percent)	10.10%	10.10%