Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies (Tables)

v2.4.0.6
Summary of Significant Accounting Policies (Tables)
 6 Months Ended
Jun. 30, 2012
Accounting Policies [Abstract]  
Changes in Allowance for Doubtful Accounts
Changes in the allowance for doubtful accounts for the six months ended June 30, 2011 and 2012 are as follows:
 
 
Six Months Ended June 30,
 
 
2011

2012
Allowance for doubtful accounts, beginning of period
 
$
1,677,278

 
$
1,135,391

Charges to costs and expenses
 
24,220

 
77,743

Account write-offs and other
 
(195,296
)
 
(111,721
)
Allowance for doubtful accounts, end of period
 
$
1,506,202

 
$
1,101,413

Estimated Useful Lives of Property and Equipment
Depreciation and amortization of property and equipment are computed on a straight-line basis over the following estimated useful lives:
Asset Classification
 
Estimated Useful Life
Furniture and office equipment
 
Five years
Computer equipment and software costs
 
Five years
Leasehold improvements
 
Lesser of term of lease or five years
Automobiles
 
Five years
Land
 
Unlimited
Basic and Diluted Earnings Per Share Calculation, Numerator and Denominator
 
Three Months Ended June 30,
 
Six Months Ended June 30,
 
2011
 
2012
 
2011
 
2012
Basic and diluted net income
$
8,832,128

 
$
5,168,868

 
$
14,120,413

 
$
6,674,166

Basic weighted-average shares outstanding
42,367,242

 
44,541,025

 
41,847,646

 
44,343,059

Effect of dilutive securities:
 

 
 

 
 
 
 
Preferred stock
—

 
—

 
—

 
—

Stock options
3,540,506

 
1,818,298

 
3,438,004

 
1,800,873

Diluted weighted-average shares outstanding
45,907,748

 
46,359,323

 
45,285,650

 
46,143,932