Quarterly report pursuant to Section 13 or 15(d)

Contingencies (Detail)

Contingencies (Detail) (USD $)
In Millions, unless otherwise specified
1 Months Ended
Nov. 30, 2012
Jun. 30, 2004
Apr. 30, 2013
Gain Contingency, Patents Allegedly Infringed upon, Number   6  
Number of Licensee Patents   4  
Gain Contingency, Patents Found Not Infringed upon, Number 1    
Additional Recovery Related to Prejudement Interest     Prejudgment interest should provide for additional recovery in the tens of millions of dollars
Indemnification Agreement [Member]
Gain Contingency, Unrecorded Amount (in Dollars)     48.5