Components for Stock-Based Compensation (Detail) (USD $) In Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation	$ 793		$ 1,934		$ 2,462		$ 4,749
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation	775		1,720		2,254		4,704
Directors restricted stock grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation	64	[1]	45	[1]	184	[1]	135	[1]
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation	1		61		124		158
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation	$ (47)	[2]	$ 108	[2]	$ (100)	[2]	$ (248)	[2]

[1] Relates to non-employee directors serving on the Parent Company's Board of Directors, all who have been elected by the Company's shareholders, as well as NUAL's Board of Directors.

[2] All issued stock appreciation rights were exercised during 2011. The Company will no longer issue awards from the Stock Appreciation Rights Plan as a result of the 2005 Amended and Restated Stock Incentive Plan.