Significant Customers that Accounted for More than Ten Percentage of Total Product Revenue (Parenthetical) (Detail)	Dec. 31, 2012
Revenue, Major Customer [Line Items]
Product revenue	10.00%

The percentage of net product revenue to total net revenue from the sale of goods as of year end.

No definition available.

Name:	us-gaap_SalesRevenueGoodsNetPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant