Consolidated Balance Sheets - USD ($)
Jun. 30, 2016
Dec. 31, 2015
Current assets:    
Cash and cash equivalents $ 40,114,570 $ 56,522,194
Accounts receivable, net of allowance for doubtful accounts of $1,536,287 and $1,627,315 at June 30, 2016 and December 31, 2015, respectively 228,663,211 196,420,614
Income taxes receivable 2,852,406 1,038,327
Prepaid expenses 4,155,683 3,605,602
Other current assets 2,132,707 3,237,227
Total current assets 277,918,577 260,823,964
Noncurrent assets:    
Property and equipment, net 32,978,314 27,304,474
Goodwill 307,314,171 308,490,588
Intangible assets, net of accumulated amortization of $34,759,406 and $26,785,810 at June 30, 2016 and December 31, 2015, respectively 139,558,573 147,532,169
Other noncurrent assets 2,242,596 2,358,587
Total noncurrent assets 482,093,654 485,685,818
Total assets 760,012,231 746,509,782
Current liabilities:    
Accounts payable 133,142,622 103,985,783
Due to seller, current 1,002,449 2,338,462
Accrued expenses 30,607,684 30,283,062
Other current liabilities 1,729,327 784,829
Total current liabilities 166,482,082 137,392,136
Noncurrent liabilities:    
Convertible notes, net 200,057,163 196,659,354
Due to seller, noncurrent 845,051 1,748,235
Other noncurrent liabilities 8,294,032 2,940,435
Deferred income taxes 15,834,584 12,520,048
Total noncurrent liabilities 225,030,830 213,868,072
Total liabilities 391,512,912 351,260,208
Stockholders' equity:    
Common stock, par value $0.0001 per share, 100,000,000 shares authorized, 30,218,653 shares issued and 28,651,997 shares outstanding at June 30, 2016; 29,765,525 shares issued and 29,727,588 shares outstanding at December 31, 2015 3,024 2,979
Treasury stock, 1,566,656 and 37,937 shares at June 30, 2016 and December 31, 2015, respectively (33,099,537) (784,829)
Additional paid-in capital 322,373,282 319,002,254
Retained earnings 79,222,550 77,029,170
Total stockholders' equity 368,499,319 395,249,574
Total liabilities and stockholders' equity $ 760,012,231 $ 746,509,782