Earnings per share (Details Textual)	3 Months Ended	6 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Earnings Per Share [Line Items]
Weighted Average Number of Shares Outstanding, Basic and Diluted	8,027,147	8,100,593	8,027,147	8,112,490

Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

No definition available.

Name:	us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration