Consumer Price Index Increase

No definition available.

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- Definition

Expiration Period, Commitments to Extend Credit

+ References

No definition available.

+ Details

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- Definition

Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability, Expiration Greater than Five Years

+ References

No definition available.

+ Details

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- Definition

Number of months in which the majority of loan commitments are expected to fund loans

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loss Contingencies [Line Items]
Number of months in which the majority of loan commitments are expected to fund loans	3 months
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating leases, future minimum payments due - 2015	$ 13.8
Operating leases, future minimum payments due - 2016	11.3
Operating leases, future minimum payments due - 2017	9.3
Operating leases, future minimum payments due - 2018	4.2
Operating leases, future minimum payments due - 2019	1.9
Operating leases, future minimum payments due - 2020 and thereafter	6.7
Consumer Price Index increase	3.00%chfc_ConsumerPriceIndexIncrease
Operating lease rent expense	12.4us-gaap_LeaseAndRentalExpense	11.6us-gaap_LeaseAndRentalExpense	10.8us-gaap_LeaseAndRentalExpense
Commitments to Extend Credit [Member]
Loss Contingencies [Line Items]
Face amount of off-balance sheet liability	1,080	878
Expiration period of commitments to extend credit	1 year
Face amount of off-balance sheet liability with expiration greater than five years	73
Commitments to Extend Credit [Member] \| Minimum [Member]
Loss Contingencies [Line Items]
Expiration period of commitments to extend credit	5 years
Standby Letters of Credit [Member]
Loss Contingencies [Line Items]
Face amount of off-balance sheet liability	41	47
Loan Origination Commitments [Member]
Loss Contingencies [Line Items]
Face amount of off-balance sheet liability	251	197
Loan Origination Commitments [Member] \| Real Estate Residential Loans [Member]
Loss Contingencies [Line Items]
Face amount of off-balance sheet liability	$ 24	$ 11