Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008	Dec. 31, 2012 U K Subsidiaries [Member]	Dec. 31, 2012 Singapore Economic Development Board [Member]	Dec. 31, 2011 Singapore Economic Development Board [Member]	Dec. 31, 2010 Singapore Economic Development Board [Member]	Dec. 31, 2009 Singapore Economic Development Board [Member]	Dec. 31, 2012 Federal [Member]	Dec. 31, 2012 State [Member]
Income Taxes [Line Items]
Deferred income taxes undistributed foreign earnings	$ 256,000,000	$ 175,000,000
Effective tax rate	35.00%								17.00%
Income tax rate									10.00%
Expiration of tax rate if agreed commitments are not met						2014
Extended tax rate expiration date if requirements are met						2018
Reduction in consolidated income taxes						2,002,000	2,030,000	1,247,000
Unrecognized tax benefits related to an acquisition	4,680,000		4,000,000	4,000,000
Increase in tax liability benefits					680,000
Net operating loss carryforwards, federal	2,518,000
Net operating loss carryforwards, state		$ 27,391,000
Net operating loss carryforwards, expire										2022 through 2027	2013 through 2021
Open tax years by major tax jurisdiction	The tax years 2008 through 2010 remain open to examination by multiple state taxing jurisdictions