Borrowing Arrangements - Additional Information (Detail) In Thousands, unless otherwise specified					12 Months Ended				12 Months Ended
	Dec. 31, 2013 USD ($)	Dec. 31, 2013 EUR (€)	Dec. 31, 2013 GBP (£)	Dec. 31, 2012 USD ($)	Dec. 31, 2013 Letter of Credit [Member] USD ($)	Dec. 31, 2013 Tax Exempt Industrial Revenue Bond One [Member] USD ($)	Dec. 31, 2013 Taxable Industrial Revenue Bond [Member] USD ($)	Dec. 31, 2013 Tax Exempt Industrial Revenue Bond Two [Member] USD ($)	Dec. 31, 2013 Minimum [Member]
Line of Credit Facility [Line Items]
Short-term lines of credit maintained	$ 9,500	€ 400	£ 3,000
Credit amount outstanding	0			0	0
Tax-exempt IRB maturing in 2020/2027/2029						4,120	7,116	2,075
Interest at a floating rate on tax-exempt IRB maturing in 2020/2027/2029						0.16%	0.20%	0.18%
Expiry date of credit facility					Aug. 01, 2015
Period for renewing the facility									1 year
Available letter of credit facility					$ 13,566