Commitments And Contingencies Information Of Term Of Operating Leases (Details)	Dec. 31, 2012	Apr. 01, 2012
Minimum lease term of operating leases	1
Maximum lease term of operating leases	10	10

Information about the leases or concessions that will expire on undeveloped acreage controlled by the enterprise.

No definition available.

Name:	CSM_MaximumLeaseTermOfOperatingLeases
Namespace Prefix:	CSM_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant