Quarterly report pursuant to Section 13 or 15(d)

Changes in Each Component of Accumulated Other Comprehensive Income (Loss) (Detail)

v3.2.0.727
Changes in Each Component of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($)
$ in Thousands
3 Months Ended
Jul. 31, 2015
Jul. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Accumulated other comprehensive income (loss), beginning balance $ (40,623) $ (2,388)
Unrealized (losses) gains arising during the period (15,636) (3,686)
Reclassification of realized net losses (gains) to net income 447 487
Accumulated other comprehensive income (loss), ending balance (55,812) (5,587)
Accumulated Translation Adjustment    
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Accumulated other comprehensive income (loss), beginning balance (20,919) 15,604
Unrealized (losses) gains arising during the period (15,632) (3,680)
Accumulated other comprehensive income (loss), ending balance (36,551) 11,924
Accumulated Defined Benefit Plans Adjustment    
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Accumulated other comprehensive income (loss), beginning balance [1] (19,708) (18,006)
Reclassification of realized net losses (gains) to net income [1] 447 487
Accumulated other comprehensive income (loss), ending balance [1] (19,261) (17,519)
Accumulated Net Unrealized Investment Gain (Loss)    
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Accumulated other comprehensive income (loss), beginning balance 4 14
Unrealized (losses) gains arising during the period $ (4) (6)
Accumulated other comprehensive income (loss), ending balance   $ 8
[1] The tax effects on the reclassifications of realized net losses was $0.3 million for both the three months ended July 31, 2015 and 2014.