Allowance for Doubtful Accounts - Additional Information (Detail)	9 Months Ended
Sep. 30, 2014 USD ($)
Polymers [Member]
Accounts Notes And Loans Receivable [Line Items]
Increased allowance for doubtful accounts	$ 3,425,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration