Investment Securities (Summary of Amortized Cost and Fair Value of Available-For-Sale Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	$ 512,740	$ 556,636	$ 677,940
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	2,581	1,468	3,646
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	1,306	4,373	942
Available-for-sale Securities, Total	514,015	553,731	680,644
US Treasury Securities [Member]
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	5,777	5,773	8,271
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	20	0	31
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	8	0
Available-for-sale Securities, Total	5,797	5,765	8,302
Government sponsored agencies [Member]
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	177,537	195,711	249,642
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	591	78	889
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	491	800	101
Available-for-sale Securities, Total	177,637	194,989	250,430
State and political subdivisions [Member]
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	14,707	14,731	31,701
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	356	395	624
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	2	6	3
Available-for-sale Securities, Total	15,061	15,120	32,322
Residential mortgage-backed securities [Member]
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	178,498	189,452	218,299
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	899	538	1,358
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	248	2,222	56
Available-for-sale Securities, Total	179,149	187,768	219,601
Collateralized Mortgage Obligations [Member]
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	118,501	133,256	133,713
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	338	111	305
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	441	1,137	718
Available-for-sale Securities, Total	118,398	132,230	133,300
Corporate bonds [Member]
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	14,832	14,825	34,925
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	0	2	136
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	124	200	64
Available-for-sale Securities, Total	14,708	14,627	34,997
Preferred stock [Member]
Available-for-sale Securities
Investment securities available-for-sale, Amortized Cost	2,888	2,888	1,389
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	377	344	303
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0	0
Available-for-sale Securities, Total	$ 3,265	$ 3,232	$ 1,692

Amortized cost and estimated fair value of investment securities.

No definition available.

Name:	chfc_AmortizedCostAndEstimatedFairValueOfInvestmentSecuritiesAbstract
Namespace Prefix:	chfc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

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

- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562

+ Details

Name:	us-gaap_AvailableForSaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CollateralizedMortgageObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CorporateBondSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_PreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: