Fair Value Of Financial Instruments (Impact of EBITDA Multiple) (Details) - Cell C [Member] $ in Thousands	12 Months Ended
	Jun. 30, 2018 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
EBITDA multiple	6.75
EBITDA Multiple 6.25 Times [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Sensitivity for fair value of investment	$ 153,724
EBITDA multiple	6.25
EBITDA Multiple 6.75 Times [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Sensitivity for fair value of investment	$ 172,948
EBITDA multiple	6.75
EBITDA Multiple 7.25 Times [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Sensitivity for fair value of investment	$ 192,172
EBITDA multiple	7.25