Net Income Per Share (Tables)

9 Months Ended

Sep. 30, 2011

Net Income Per Share [Abstract]

Calculation Of Net Income Per Share

	Three Months Ended September 30,				Nine Months Ended September 30,
	2011		2010		2011		2010
Basic net income per share:
Net income	$	44,168	$	20,624	$	107,298	$	41,279
Income allocated to participating securities—basic		615		525		1,564		1,849
Net income available to common stockholders—basic	$	43,553	$	20,099	$	105,734	$	39,430
Basic weighted average shares		139,449		142,230		141,118		143,182
Basic net income per share	$	.31	$	.14	$	.75	$	.28
Diluted net income per share:
Net income	$	44,168	$	20,624	$	107,298	$	41,279
Income allocated to participating securities—diluted		612		525		1,558		1,849
Net income available to common stockholders—diluted	$	43,556	$	20,099	$	105,740	$	39,430
Basic weighted average shares		139,449		142,230		141,118		143,182
Dilutive effect of potential common shares		984		770		1,255		1,145
Diluted weighted average shares		140,433		143,000		142,373		144,327
Diluted net income per share	$	.31	$	.14	$	.74	$	.27

Antidilutive Securities Excluded From Computation Of Earnings Per Share

	Three Months Ended September 30,				Nine Months Ended September 30,
	2011		2010		2011		2010
Total number of anti-dilutive potential common shares		2,996		2,096		764		782