Fair Value Measurement - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010		Dec. 31, 2009	Dec. 31, 2011 Corporate Bond Securities	Dec. 31, 2011 Unsecured Senior Notes	Dec. 31, 2011 Fixed rate senior notes $450 million due August 2021	Dec. 31, 2011 Estimate of Fair Value, Fair Value Disclosure	Dec. 31, 2010 Estimate of Fair Value, Fair Value Disclosure	Dec. 31, 2011 Carrying (Reported) Amount, Fair Value Disclosure	Dec. 31, 2010 Carrying (Reported) Amount, Fair Value Disclosure	Dec. 31, 2011 Tranche C Unsecured Senior Notes	Dec. 31, 2011 Tranche B Unsecured Senior Notes	Dec. 31, 2011 Tranche A Unsecured Senior Notes	Feb. 28, 2010 Private Placement Notes	Dec. 31, 2011 Private Placement Notes U.S. Dollar Denominated Expiring March 2016	Dec. 31, 2010 Private Placement Notes U.S. Dollar Denominated Expiring March 2016	Dec. 31, 2011 Fixed Rate Senior Notes U.S. Dollar Denominated Due August 2016
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Long-term debt	$ 1,491,419,000	$ 606,493,000					$ 448,497,000	$ 1,512,500,000	$ 611,200,000	$ 1,491,400,000	$ 606,500,000					$ 254,512,000	$ 250,000,000	$ 299,603,000
Senior Notes						$ 1,000,000,000						$ 450,000,000	$ 300,000,000	$ 250,000,000	$ 250,000,000
Debt, fixed rate							4.10%					4.125%	2.75%		4.10%	4.10%	4.10%	2.80%
DIO Corporation's stock volatility factor	24.00%	22.00%	[1]	22.00%	40.00%
Discount rate					15.00%
Probability-weighted average payout discount using market rate	5.00%

[1] In 2010, the Human Resources Committee of the Company’s Board of Directors reviewed the Company’s practices for NQSO grants and determined that it would be more appropriate to make all regular equity grants in the February time frame, after the Company’s financial results are known for the prior year. Accordingly, there were no grants of NQSO in December 2010, which had been the historic practice.