Earnings Per Share (Tables)

6 Months Ended

Jan. 31, 2013

Earnings Per Share [Abstract]

Schedule of numerators and denominators used in basic and diluted EPS calculations

	Three months ended January 31,			Six months ended January 31,
	2013		2012	2013	2012
Numerator:
Net income for basic calculation	$	2,365,000	5,821,000	9,800,000	18,422,000
Effect of dilutive securities:
Interest expense (net of tax) on 3.0% convertible senior notes	—		1,117,000	2,234,000	2,234,000
Numerator for diluted calculation	$	2,365,000	6,938,000	12,034,000	20,656,000
Denominator:
Denominator for basic calculation	17,300,000		20,087,000	17,340,000	21,672,000
Effect of dilutive securities:
Stock-based awards	101,000		228,000	105,000	200,000
Conversion of 3.0% convertible senior notes	—		5,741,000	5,949,000	5,716,000
Denominator for diluted calculation	17,401,000		26,056,000	23,394,000	27,588,000