Short-Term Facilities (Narrative) (Details) ZAR in Millions, $ in Millions, ₩ in Billions	12 Months Ended
	Jun. 30, 2016 KRW (₩)	Jun. 30, 2016 ZAR	Jun. 30, 2016 USD ($)	Jun. 30, 2015 ZAR	Jun. 30, 2015 USD ($)
South African Credit Facility [Member]
Short-term Debt [Line Items]
Maximum borrowing capacity | ZAR		ZAR 150.0
Amount utilized		131.1	$ 8.9	ZAR 139.6	$ 11.4
South African Credit Facility [Member] | Nedbank Limited [Member]
Short-term Debt [Line Items]
Aggregate amount		400.0	27.1
Primary amount, available immediately		200.0	13.5
Secondary amount, not available immediately		ZAR 200.0	13.5
Bank Overdrafts Facility [Member]
Short-term Debt [Line Items]
Amount utilized			$ 0.0		0.0
Short term interest rate	9.35%	9.35%	9.35%
Commitment fee percentage	0.35%
Bank Overdrafts Facility [Member] | Nedbank Limited [Member]
Short-term Debt [Line Items]
Maximum borrowing capacity		ZAR 50.0	$ 3.4
Derivative Facilities [Member] | Nedbank Limited [Member]
Short-term Debt [Line Items]
Maximum borrowing capacity		ZAR 150.0	10.1
South Korea, Hana Bank Overdraft Facility [Member]
Short-term Debt [Line Items]
Maximum borrowing capacity	₩ 10		8.7
Amount utilized			$ 0.0		$ 0.0
Initiation date	Jan. 01, 2014
Renewal period	1 year
New expiration date	Jan. 01, 2017
Overdraft rate	3.31%	3.31%	3.31%