Consolidated Statements of Operations (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Income Statement [Abstract]    
Revenue $ 5,979,260 $ 4,914,479
Cost of revenue 5,600,506 4,599,817
Gross profit 378,754 314,662
Expenses:    
Selling, general and administrative 151,367 130,519
Depreciation of property and equipment 15,808 12,368
Amortization of intangible assets 52,619 54,986
Total operating expenses 219,794 197,873
Operating income 158,960 116,789
Interest and other expense, net 15,495 11,336
Income before income taxes 143,465 105,453
Income tax expense 43,911 28,108
Net income 99,554 77,345
Less: Net income attributable to non-controlling interest 12,861 13,900
Net income attributable to the Company $ 86,693 $ 63,445
Earnings per share attributable to the Company:    
Basic (in dollars per share) $ 0.42 $ 0.31
Diluted (in dollars per share) $ 0.42 $ 0.31
Weighted average number of shares used in computing earnings per share:    
Basic (in shares) 207,641,523 206,525,188
Diluted (in shares) 208,289,689 207,086,677