Consolidated Balance Sheets - USD ($)
Jun. 30, 2017
Dec. 31, 2016
Current assets:    
Cash and cash equivalents $ 20,030,667 $ 16,646,089
Accounts receivable, net of allowance for doubtful accounts of $3,665,289 and $3,018,995 at June 30, 2017 and December 31, 2016, respectively 267,684,238 231,430,645
Income taxes receivable 10,823,956 7,757,841
Prepaid expenses 7,280,421 7,856,366
Other current assets 4,034,373 4,609,933
Total current assets 309,853,655 268,300,874
Noncurrent assets:    
Property and equipment, net 60,246,353 57,450,059
Goodwill 307,314,171 307,314,171
Intangible assets, net of accumulated amortization of $49,734,255 and $42,590,238 at June 30, 2017 and December 31, 2016, respectively 124,583,724 131,727,741
Other noncurrent assets 1,757,499 1,975,071
Total noncurrent assets 493,901,747 498,467,042
Total assets 803,755,402 766,767,916
Current liabilities:    
Accounts payable 178,703,977 135,386,424
Due to seller, current 814,500 743,600
Accrued expenses 30,309,114 31,810,671
Total current liabilities 209,827,591 167,940,695
Noncurrent liabilities:    
Convertible notes, net 207,183,398 203,564,011
Due to seller, noncurrent 555,500 956,400
Other noncurrent liabilities 20,394,496 19,487,942
Deferred income taxes 17,923,514 16,669,138
Total noncurrent liabilities 246,056,908 240,677,491
Total liabilities 455,884,499 408,618,186
Stockholders' equity:    
Common stock, par value $0.0001 per share, 100,000,000 shares authorized, 30,611,449 shares issued and 27,760,067 shares outstanding at June 30, 2017; 30,421,273 shares issued and 28,131,479 shares outstanding at December 31, 2016 3,063 3,045
Treasury stock, 2,851,382 and 2,289,794 shares at June 30, 2017 and December 31, 2016, respectively (59,999,981) (49,148,912)
Additional paid-in capital 332,366,382 328,676,749
Retained earnings 75,501,439 78,618,848
Total stockholders' equity 347,870,903 358,149,730
Total liabilities and stockholders' equity $ 803,755,402 $ 766,767,916