Earnings per Share (Tables)

9 Months Ended

Jun. 30, 2011

Earnings Per Share [Abstract]

Net components of basic and diluted earnings per share

	Three Months Ended				Nine Months Ended
	June 30,				June 30,
	2011		2010		2011		2010
Net income (A)	$	26,527	$	19,962	$	85,794	$	69,442
Weighted average outstanding shares of common stock (B)		49,926		49,201		49,849		48,969
Dilutive effect of stock options and restricted stock		459		439		443		572
Weighted average common stock and common stock equivalents (C)		50,385		49,640		50,292		49,541
Basic earnings per share (A/B)	$	0.53	$	0.41	$	1.72	$	1.42
Diluted earnings per share (A/C)	$	0.53	$	0.40	$	1.71	$	1.40
Potential common shares excluded from the calculation of diluted earnings per share		—		5		6		6