Net Income Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Numerator:
Net income	$ 11,446	$ 13,496	$ 41,844	$ 49,873
Denominator:
Shares, basic	33,389	33,992	32,935	34,118
Effect of dilutive share-based awards	1,790	1,354	1,439	1,447
Shares, diluted	35,179	35,346	34,374	35,565
Net income per share:
Basic	$ 0.34	$ 0.40	$ 1.27	$ 1.46
Diluted	$ 0.33	$ 0.38	$ 1.22	$ 1.40