Sales of Accounts Receivable and Receivable Discount Program - Additional Information (Detail) (Trade Accounts Receivable [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Trade Accounts Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sale of accounts receivable	$ 5,712	$ 20,121
Pre-tax loss on accounts receivable	$ 17	$ 42