Assets Held for Sale - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Assets Held For Sale [Line Items]
Net property, plant and equipment at its Brazil facility to assets held for sale	$ 7.9
Inventories and supply parts at its Brazil facility	$ 3.6

Carrying amount as of the balance sheet date of inventories classified as held for sale that are segregated from normal operations and that are anticipated to be sold within one year (or in the operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

Name:	us-gaap_InventoriesPropertyHeldForSaleCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant