Net Income Per Share

12 Months Ended

Dec. 31, 2011

Earnings Per Share [Abstract]

Net Income Per Share

Net Income Per Share

Net income per share is presented as basic and diluted net income per share. Basic net income per share is net income available to common stockholders divided by the weighted average number of common shares outstanding. Diluted net income per share is similar to basic net income per share, except that the denominator includes potential common shares that, had they been issued, would have had a dilutive effect.

The following summarizes the elements included in the calculation of basic and diluted net income per share for 2011, 2010 and 2009:

	Year ended December 31,
	2011		2010		2009
Net income	$	48,150	$	190,837	$	16,245
Weighted average shares outstanding—Basic	164,256		155,870		149,759
Dilutive securities	8,254		7,616		2,567
Weighted average shares outstanding—Dilutive	172,510		163,486		152,326
Net income per common share:
Basic	$	0.29	$	1.22	$	0.11
Diluted	$	0.28	$	1.17	$	0.11

Options and other exercisable convertible securities excluded from the calculation as their effect would have been antidilutive are as follows:

	Year ended December 31,
	2011	2010	2009
Antidilutive securities	6,174	10,392	23,727