Borrowings (Summary Of Short-Term Credit Facilities) (Details) $ in Thousands, R in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 ZAR (R)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 ZAR (R)	Nov. 02, 2020 ZAR (R)	Nov. 01, 2020 ZAR (R)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 ZAR (R)
Short-term Debt [Line Items]
Short-term facility available	$ 113,162		$ 113,162
Utilized	137,333	$ 207,876	206,479		$ 391,550
Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	98,904		98,904
Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	3,410		3,410
Balance as of June 30, 2019			14,814
Utilized			206,479
Repaid			(165,108)
Foreign currency adjustment			4,618
Balance as of September 30, 2019	60,803		60,803
Overdraft Facility [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Balance as of September 30, 2019	60,803		60,803
Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	10,848		10,848
Balance as of June 30, 2019			5,398
Foreign currency adjustment			1,455
Balance as of September 30, 2019	10,679		10,679
Nedbank Limited [Member] | Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	20,500		20,500			R 300.0
Nedbank Limited [Member] | Overdraft Facility [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	17,100		17,100			250.0
Nedbank Limited [Member] | Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	10,800		10,800			R 159.0
South Africa [Member] | Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Utilized			3,826
South Africa [Member] | Amended July 2017 [Member] | Overdraft Facility [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Balance as of September 30, 2019	$ 53,734		$ 53,734
South Africa [Member] | Nedbank Limited [Member] | Prime Rate [Member]
Short-term Debt [Line Items]
Debt instrument, interest rate	5.85%		5.85%			5.85%
Percentage used to calculate interest rate on short-term facilities	1.15%		1.15%			1.15%
South Africa [Member] | Nedbank Limited [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	$ 17,052		$ 17,052
South Africa [Member] | Nedbank Limited [Member] | Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	3,410		3,410
Balance as of June 30, 2019			58
Utilized			16,551
Repaid			(9,438)
Foreign currency adjustment			(102)
Balance as of September 30, 2019	7,069		7,069
South Africa [Member] | Nedbank Limited [Member] | Overdraft Facility [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	31,310		31,310
Balance as of September 30, 2019	7,069		7,069
South Africa [Member] | Nedbank Limited [Member] | Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	10,848		10,848				R 159.0	R 150.0	$ 150,000	R 159.0
Balance as of June 30, 2019			5,398
Utilized			3,826
Foreign currency adjustment			1,455
Balance as of September 30, 2019	10,679		10,679
South Africa [Member] | Nedbank Limited [Member] | Indirect And Derivative Facilities [Member] | Nedbank Short-Term Credit Facility [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019			5,400	R 93.6
Balance as of September 30, 2019	10,700		10,700	R 156.6
South Africa [Member] | RMB [Member]
Short-term Debt [Line Items]
Short-term facility available	$ 81,852		$ 81,852
South Africa [Member] | RMB [Member] | Prime Rate [Member]
Short-term Debt [Line Items]
Debt instrument, interest rate	7.00%		7.00%			7.00%
South Africa [Member] | RMB [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	$ 81,852		$ 81,852
South Africa [Member] | RMB [Member] | Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	0		0
Balance as of June 30, 2019			14,756
Utilized			189,928
Repaid			(155,670)
Foreign currency adjustment			4,720
Balance as of September 30, 2019	53,734		53,734
South Africa [Member] | RMB [Member] | Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	0		0
Balance as of June 30, 2019			0
Utilized			0
Foreign currency adjustment			0
Balance as of September 30, 2019	$ 0		$ 0