Fair Value Measurements - Aggregate Fair Value, Contractual Balance, and Gain or Loss for Loans Held-For-Sale (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Aggregate fair value	$ 23,535	$ 85,030
Contractual balance	22,660	82,080
Unrealized gain	$ 875	$ 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