Fair Value Measurements - Aggregate Fair Value, Contractual Balance, and Gain or Loss for Loans Held-For-Sale (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Aggregate fair value	$ 33,019	$ 85,030
Contractual balance	31,799	82,080
Unrealized gain	$ 1,220	$ 2,950

Represents the amount of unrealized gain (loss) of loans held for investment.

No definition available.

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