XML 35 R23.htm IDEA: XBRL DOCUMENT v2.4.0.6
Investments (Details Textual) (USD $)
3 Months Ended 6 Months Ended 12 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Mar. 31, 2013
Mar. 31, 2012
Sep. 30, 2012
Investments (Textual) [Abstract]          
Maturity of short-term investments less than one year       less than one year
Maturity of long-term investments greater than one year       greater than one year
Other-than-temporary impairment charges recognized $ 0 $ 0 $ 0 $ 0