XML 47 R41.htm IDEA: XBRL DOCUMENT  v2.3.0.11
Incentive Plans - Additional Information (Detail) (USD $)
1 Months Ended 6 Months Ended 12 Months Ended 1 Months Ended
Feb. 28, 2011
Jun. 30, 2011
Jun. 30, 2010
Dec. 31, 2007
Annual Incentive Plan, 2007 Annual Plan
Dec. 31, 2007
Employee Stock Purchase Plan
Feb. 28, 2011
Stock Options
Feb. 28, 2011
Performance-Based Restricted Stock
Feb. 28, 2011
Performance-Based Restricted Stock
Minimum
Feb. 28, 2011
Performance-Based Restricted Stock
Maximum
Feb. 28, 2011
Time-Lapse Restricted Stock
Compensation Related Costs Share Based Payments Disclosure [Line Items]                    
Maximum number of shares available for issuance       6,700,000 980,000          
Maximum number of shares available for issuance, Annual Rate       1.00%            
Granted stock options 1,397,312                  
Granted stock options, exercise price $ 67.635                  
Granted stock options, valuation per option $ 20.34                  
Granted restricted stock             521,423     29,115
Granted restricted stock, valuation               $ 38.94 $ 64.89 $ 67.64
Stock award, valuation method           Black-Scholes valuation model Monte Carlo valuation model      
Employee Stock purchase plan, vesting scheme                   These shares vest on the third anniversary of the date of grant.
Proceeds from exercise of stock options and employee stock purchase plans   $ 7,900,000 $ 14,798,000              
Income tax benefit realized for the tax deductions from option exercises   $ 7,400,000 $ 5,900,000