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)
 9 Months Ended
Sep. 30, 2012
Accounting Policies [Abstract]  
Changes in Allowance for Doubtful Accounts
Changes in the allowance for doubtful accounts for the nine months ended September 30, 2011 and 2012 are as follows:
 
 
Nine Months Ended September 30,
 
 
2011

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

 
$
1,135,391

Charges to costs and expenses
 
24,374

 
83,767

Account write-offs and other
 
4,915

 
(124,634
)
Allowance for doubtful accounts, end of period
 
$
1,706,567

 
$
1,094,524

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 September 30,
 
Nine Months Ended September 30,
 
2011
 
2012
 
2011
 
2012
Basic and diluted net income
$
12,358,580

 
$
6,771,182

 
$
26,478,993

 
$
13,445,348

Basic weighted-average shares outstanding
43,116,861

 
44,788,160

 
42,275,367

 
44,492,509

Effect of dilutive securities:
 

 
 

 
 
 
 
Preferred stock
—

 
—

 
—

 
—

Stock options
3,191,171

 
1,459,079

 
3,101,737

 
1,517,629

Diluted weighted-average shares outstanding
46,308,032

 
46,247,239

 
45,377,104

 
46,010,138