Borrowings (Summary Of Short-Term Credit Facilities) (Details) R in Millions	12 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2020 ZAR (R)	Jun. 30, 2019 USD ($)		Jun. 30, 2018 USD ($)		Feb. 04, 2019 USD ($)	Sep. 14, 2018 USD ($)
Short-term Debt [Line Items]
Short-term facility available	$ 95,197,000
Utilized	689,763,000		$ 822,754,000	[1]	$ 44,900,000	[1]
Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	83,658,000
Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	2,885,000
Balance as of June 30, 2019	84,990,000		0
Utilized	689,763,000		822,754,000
Repaid	(747,935,000)		(740,969,000)
Foreign currency adjustment	(12,004,000)		3,205,000
Balance as of September 30, 2019	14,814,000		84,990,000		0
Overdraft Facility [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019	75,446,000
Balance as of September 30, 2019	14,814,000		75,446,000
Overdraft Facility [Member] | No Restrictions As To Use [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019	9,544,000
Balance as of September 30, 2019	0		9,544,000
Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	8,654,000
Balance as of June 30, 2019	6,643,000		7,871,000
Guarantees cancelled	0		(1,075,000)
Utilized	0		46,000
Foreign currency adjustment	(1,245,000)		(199,000)
Balance as of September 30, 2019	5,398,000		6,643,000		7,871,000
South Africa [Member] | Overdraft Facility [Member] | Nedbank Short-Term Credit Facility [Member]
Short-term Debt [Line Items]
Total overdraft facilities withdrawn			8,600,000
Net of total overdraft facilities withdrawn			5,900,000
Total funds in bank accounts			2,700,000
South Africa [Member] | Amended July 2017 [Member]
Short-term Debt [Line Items]
Short-term facility available	69,234,000
South Africa [Member] | Amended July 2017 [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	69,234,000
South Africa [Member] | Amended July 2017 [Member] | Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	0
Balance as of June 30, 2019	69,566,000		0
Utilized	603,134,000		722,375,000
Repaid	(647,990,000)		(655,612,000)
Foreign currency adjustment	(9,954,000)		2,803,000
Balance as of September 30, 2019	14,756,000		69,566,000		0
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 June 30, 2019	69,566,000
Balance as of September 30, 2019	14,756,000		69,566,000
South Africa [Member] | Amended July 2017 [Member] | Overdraft Facility [Member] | No Restrictions As To Use [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019	0
Balance as of September 30, 2019	0		0
South Africa [Member] | Amended July 2017 [Member] | Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	0
Balance as of June 30, 2019	0		0
Guarantees cancelled	0		0
Utilized	0		0
Foreign currency adjustment	0		0
Balance as of September 30, 2019	0		0		0
South Africa [Member] | Nedbank Limited [Member]
Short-term Debt [Line Items]
Short-term facility available	25,963,000
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	14,424,000
South Africa [Member] | Nedbank Limited [Member] | Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	2,885,000
Balance as of June 30, 2019	5,880,000		0
Utilized	69,245,000		85,843,000
Repaid	(73,017,000)		(80,365,000)
Foreign currency adjustment	(2,050,000)		402,000
Balance as of September 30, 2019	58,000		5,880,000		0
South Africa [Member] | Nedbank Limited [Member] | Overdraft Facility [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019	5,880,000
Balance as of September 30, 2019	58,000		5,880,000
South Africa [Member] | Nedbank Limited [Member] | Overdraft Facility [Member] | No Restrictions As To Use [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019	0
Balance as of September 30, 2019	0		0
South Africa [Member] | Nedbank Limited [Member] | Overdraft Facility [Member] | Nedbank Short-Term Credit Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	12,400,000
Net of total overdraft facilities withdrawn	100,000
South Africa [Member] | Nedbank Limited [Member] | Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	8,654,000
Balance as of June 30, 2019	6,643,000		7,871,000
Guarantees cancelled	0		(1,075,000)
Utilized	0		46,000
Foreign currency adjustment	(1,245,000)		(199,000)
Balance as of September 30, 2019	5,398,000		6,643,000		7,871,000
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	6,600,000	R 93.6
Balance as of September 30, 2019	5,400,000	R 93.6	6,600,000
United States [Member] | Bank Frick [Member]
Short-term Debt [Line Items]
Short-term facility available	0
United States [Member] | Bank Frick [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Short-term facility available	0
United States [Member] | Bank Frick [Member] | Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available	0						$ 20,000,000
Balance as of June 30, 2019	9,544,000		0
Utilized	17,384,000		14,536,000
Repaid	(26,928,000)		(4,992,000)
Foreign currency adjustment	0		0
Balance as of September 30, 2019	0		9,544,000		0
United States [Member] | Bank Frick [Member] | Overdraft Facility [Member] | Overdraft Restricted As To Use For ATM Funding Only [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019	0
Balance as of September 30, 2019	0		0
United States [Member] | Bank Frick [Member] | Overdraft Facility [Member] | No Restrictions As To Use [Member]
Short-term Debt [Line Items]
Balance as of June 30, 2019	9,544,000
Balance as of September 30, 2019	0		9,544,000
United States [Member] | Bank Frick [Member] | Indirect And Derivative Facilities [Member]
Short-term Debt [Line Items]
Short-term facility available	0
Balance as of June 30, 2019	0		0
Guarantees cancelled	0		0
Utilized	0		0
Foreign currency adjustment	0		0
Balance as of September 30, 2019	0		$ 0		$ 0
United States [Member] | Bank Frick [Member] | Renewed [Member] | Overdraft Facility [Member]
Short-term Debt [Line Items]
Short-term facility available								$ 10,000,000
Balance as of September 30, 2019	$ 13,900,000

[1] Certain amounts have been restated to correct the misstatement discussed in Note 1