Net Income Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Net Income Per Share [Abstract]

Calculation Of Net Income Per Share

	Years Ended December 31,
	2011		2010		2009
Basic net income per share:
Net income	$	149,922	$	66,069	$	37,263
Income allocated to participating securities		2,159		2,340		2,196
Net income available to common stockholders	$	147,763	$	63,729	$	35,067
Basic weighted average shares		140,479		142,833		145,912
Basic net income per share	$	1.05	$	.45	$	.24
Diluted net income per share:
Net income	$	149,922	$	66,069	$	37,263
Income allocated to participating securities		2,150		2,340		2,196
Net income available to common stockholders	$	147,772	$	63,729	$	35,067
Basic weighted average shares		140,479		142,833		145,912
Dilutive effect of potential common shares		1,311		1,195		699
Diluted weighted average shares		141,790		144,028		146,611
Diluted net income per share	$	1.04	$	.44	$	.24