Business Combinations Pro Forma Information (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended 6 Months Ended
Jun. 30, 2012
Jun. 30, 2012
Business Acquisition, Pro Forma Information [Abstract]    
Revenue $ 3,246,828 $ 6,418,355
Gross profit 210,039 419,961
Net income $ 18,020 $ 46,139
Earnings per share attributable to the Company:    
Basic (in dollars per share) $ 0.09 $ 0.22
Diluted (in dollars per share) $ 0.08 $ 0.22
Weighted average number of shares used in computing earnings per share:    
Basic (in shares) 211,181,678 207,489,500
Diluted (in shares) 212,509,422 208,870,728