Supplemental equity information (Details Textual) (Economic Modeling [Member])	Aug. 31, 2012
Economic Modeling [Member]
Supplemental equity information (Textual) [Abstract]
Percentage of acquired company	74.00%
Shareholders for remaining of ownership percentage	26.00%

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant