Common Stock (Details) In Millions, except Share data, unless otherwise specified	0 Months Ended		1 Months Ended		12 Months Ended
	Jul. 28, 2009 USD ($)	Jul. 28, 2009 ZAR	May 31, 2010 USD ($)	Feb. 28, 2010 USD ($)	Jun. 30, 2012 USD ($)	Jun. 30, 2011 USD ($)
Common Stock [Abstract]
Number of votes per common share					1
Stock repurchase program, authorized amount			$ 50	$ 50	$ 100
Common stock repurchased, shares	9,221,526	9,221,526			180,656	125,392
Aggregate purchase price of common stock	$ 124.5	977.3			$ 1.1	$ 1.0
Common stock repurchase per share	$ 13.50	105.98
Number of shareholders of which common stock was repurchased from	2	2