Quarterly report pursuant to Section 13 or 15(d)

Investments - Additional Information (Detail)

v2.4.0.8
Investments - Additional Information (Detail)
6 Months Ended
Sep. 30, 2014
Minimum [Member]
 
Investment Securities [Line Items]  
Treasury with original maturities period 3 months
Maximum [Member]
 
Investment Securities [Line Items]  
Investment maturity date range end May 13, 2015
Treasury with original maturities period 1 year