Three Months Ended June 30, 

Six Months Ended June 30, 

2018

2017

2018

2017

Net income - basic and diluted

$

27,153

$

23,460

$

53,540

$

21,749

Weighted average number of common shares outstanding - basic

35,102,429

36,488,222

35,081,292

36,803,979

Dilutive effect of common stock equivalents:

RSAs with service-based conditions

165,951

227,185

174,537

214,242

RSAs with market-based conditions

253,382

189,835

241,552

160,693

RSAs with performance-based conditions

 —

 —

 —

 —

Stock options

315,340

286,057

330,909

225,279

Weighted average number of common shares outstanding - diluted

35,837,102

37,191,299

35,828,290

37,404,193

Basic net income per common share

$

0.77

$

0.64

$

1.53

$

0.59

Diluted net income per common share

$

0.76

$

0.63

$

1.49

$

0.58