Subsequent Event - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Subsequent Event [Line Items]
Percentage of equity	2.00%
Minimum [Member]
Subsequent Event [Line Items]
Estimated understatement of inventory and customer deposits	250
Estimated impact on retained earnings, net of deferred taxes	20
Maximum [Member]
Subsequent Event [Line Items]
Estimated understatement of inventory and customer deposits	350
Estimated impact on retained earnings, net of deferred taxes	40