Quarterly Operating Results (Schedule Of Unaudited Quarterly Results Of Operations) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2010
Selected Quarterly Financial Information [Abstract]
Sales Revenue, Services, Net	$ 392,611	$ 355,992	$ 333,170	$ 314,735	$ 310,524	$ 301,396	$ 304,359	$ 295,820	$ 1,396,508	$ 1,212,099	$ 1,131,039
Gross profit	112,500	114,547	105,071	92,561	97,478	105,791	104,870	106,176	424,679	414,315	405,030
Income from operations	25,539	28,217	22,596	12,450	1,561	21,865	28,204	30,000	88,802	81,630	83,109
Net income	$ 17,788	$ 22,869	$ 12,940	$ 9,561	$ (1,571)	$ 15,734	$ 16,832	$ 17,791	$ 63,158	$ 48,786	$ 41,542
Diluted earnings per share	$ 0.29	$ 0.38	$ 0.21	$ 0.16	$ (0.03)	$ 0.26	$ 0.28	$ 0.30	$ 1.05	$ 0.81	$ 0.71