Accumulated Other Comprehensive Loss (Textual) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Accumulated Other Comprehensive Loss (Textual) [Abstract]
Net unrealized gains (losses) on investment securities-available-for-sale, tax expense (benefit)	$ 1,182	$ (1,017)	$ 148
Pension and other postretirement benefits adjustment, tax benefit	$ 15,020	$ 14,616	$ 16,601

Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax Expense

No definition available.

Name:	chfc_AccumulatedOtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxExpense
Namespace Prefix:	chfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant