Net Income Per Share (Tables)

3 Months Ended

Mar. 31, 2012

Net Income Per Share [Abstract]

Calculation Of Net Income Per Share

	Three Months Ended March 31,
	2012		2011
Basic net income per share:
Net income	$	48,334	$	26,705
Income allocated to participating securities—basic		265		413
Net income available to common stockholders—basic	$	48,069	$	26,292
Basic weighted average shares		139,384		142,653
Basic net income per share	$	.34	$	.18
Diluted net income per share:
Net income	$	48,334	$	26,705
Income allocated to participating securities—diluted		264		412
Net income available to common stockholders—diluted	$	48,070	$	26,293
Basic weighted average shares		139,384		142,653
Dilutive effect of potential common shares		1,059		1,483
Diluted weighted average shares		140,443		144,136
Diluted net income per share	$	.34	$	.18

Antidilutive Securities Excluded From Computation Of Earnings Per Share

	Three Months Ended March 31,
	2012		2011
Total number of anti-dilutive potential common shares		752		184