Regulatory Capital (Tables)

6 Months Ended

Jun. 30, 2013

Banking and Thrift [Abstract]

Corporation's and Chemical Bank's actual capital amounts and ratios with the quantitative measures established by regulation to ensure capital adequacy

The summary below compares the Corporation’s and Chemical Bank’s actual capital amounts and ratios with the quantitative measures established by regulation to ensure capital adequacy:

	Actual				Minimum Required for Capital Adequacy Purposes				Required to be Well Capitalized Under Prompt Corrective Action Regulations
	Capital Amount		Ratio		Capital Amount		Ratio		Capital Amount		Ratio
	(Dollars in thousands)
June 30, 2013
Total Capital to Risk-Weighted Assets:
Corporation	$	572,503	13.1	%	$	348,442	8.0	%	N/A		N/A
Chemical Bank	556,536		12.8		347,865		8.0		$	434,831	10.0	%
Tier 1 Capital to Risk-Weighted Assets:
Corporation	517,716		11.9		174,221		4.0		N/A		N/A
Chemical Bank	501,839		11.5		173,932		4.0		260,899		6.0
Leverage Ratio:
Corporation	517,716		9.1		228,436		4.0		N/A		N/A
Chemical Bank	501,839		8.8		228,126		4.0		285,157		5.0
December 31, 2012
Total Capital to Risk-Weighted Assets:
Corporation	$	552,171	13.2	%	$	334,140	8.0	%	N/A		N/A
Chemical Bank	536,223		12.9		333,195		8.0		$	416,494	10.0	%
Tier 1 Capital to Risk-Weighted Assets:
Corporation	499,563		12.0		167,070		4.0		N/A		N/A
Chemical Bank	483,761		11.6		166,598		4.0		249,896		6.0
Leverage Ratio:
Corporation	499,563		9.2		217,145		4.0		N/A		N/A
Chemical Bank	483,761		8.9		216,784		4.0		270,980		5.0
June 30, 2012
Total Capital to Risk-Weighted Assets:
Corporation	$	542,827	13.6	%	$	319,863	8.0	%	N/A		N/A
Chemical Bank	535,868		13.4		319,236		8.0		$	399,045	10.0	%
Tier 1 Capital to Risk-Weighted Assets:
Corporation	492,395		12.3		159,931		4.0		N/A		N/A
Chemical Bank	485,533		12.2		159,618		4.0		239,427		6.0
Leverage Ratio:
Corporation	492,395		9.4		208,808		4.0		N/A		N/A
Chemical Bank	485,533		9.3		208,778		4.0		260,973		5.0