XML 95 R91.htm IDEA: XBRL DOCUMENT v2.4.0.8
Summary of Performance Units Activity (Parenthetical) (Detail) (Performance Units)
Sep. 30, 2013
Performance Units
 
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Performance Share Units [Line Items]  
Percentage change on achievement of performance goals 22.20%
Percentage Change on achievement of performance goals 27.80%