Unaudited Quartely Results (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
Unaudited Quarterly Results [Abstract]
Revenue	$ 107,616	$ 90,664	$ 92,058	$ 99,926	$ 97,368	$ 92,758	$ 89,011	$ 64,283	$ 390,264	$ 343,420	$ 280,364
Operating (loss) income	(2,402)	12,478	20,228	30,846	26,593	(22,125)	21,974	10,986	61,150	37,428	69,811
Net (loss) income attributable to Net 1	$ (7,977)	$ 7,766	$ 25,094	$ 19,768	$ 6,832	$ (21,562)	$ 9,948	$ 7,429	$ 44,651	$ 2,647	$ 38,990
Basic (loss) earnings per share, in $	$ (0.17)	$ 0.17	$ 0.56	$ 0.44	$ 0.15	$ (0.47)	$ 0.22	$ 0.16	$ 0.99	$ 0.06	$ 0.84
Diluted (loss) earnings per share, in $	$ (0.17)	$ 0.17	$ 0.56	$ 0.44	$ 0.15	$ (0.47)	$ 0.22	$ 0.16	$ 0.99	$ 0.06	$ 0.84