XML 24 R52.htm IDEA: XBRL DOCUMENT v2.4.0.6
Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)
In Thousands, unless otherwise specified
6 Months Ended 12 Months Ended
Jun. 30, 2012
Dec. 31, 2011
Cash and Cash Equivalents
   
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Cash $ 44,000 $ 499
Money market funds 471,121 155,814
Accrued Liabilities
   
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Treasury lock   48,829
Fair Value, Inputs, Level 1 | Cash and Cash Equivalents
   
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Cash 44,000 499
Money market funds 471,121 155,814
Fair Value, Inputs, Level 2 | Accrued Liabilities
   
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Treasury lock   $ 48,829