Common Stock (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	May 19, 2020	Apr. 11, 2016	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018	Feb. 05, 2020
Class Of Stock [Line Items]
Common stock, par value			$ 0.001	$ 0.001
Executed Under Share Repurchase Authorizations [Member] | Common Stock [Member]
Class Of Stock [Line Items]
Shares repurchased			0	0	0
Executed Under Share Repurchase Authorizations [Member] | Maximum [Member] | Common Stock [Member]
Class Of Stock [Line Items]
Stock repurchase program authorized amount						$ 100.0
IFC Investors [Member]
Class Of Stock [Line Items]
Number of trading days preceding triggering event		60 days
IFC Investors [Member] | Minimum [Member]
Class Of Stock [Line Items]
Percentage of common stock ownership for right to nominate one director		5.00%
Percentage of common stock ownership for right to appoint observer		2.50%
IFC Investors [Member] | Preemptive Rights [Member]
Class Of Stock [Line Items]
Percentage of ownership for right to purchase pro-rata share		5.00%
IFC Investors [Member] | Subscription Agreement [Member]
Class Of Stock [Line Items]
Number of shares sold		9,980,000
Common stock, par value		$ 0.001
Common stock repurchase per share		$ 10.79
Cash consideration received on transaction		$ 107.7
IFC Investors [Member] | Put Option [Member] | Maximum [Member]
Class Of Stock [Line Items]
Percentage of ownership to adopt shareholder rights plan		20.00%
Africa Capitalization Fund, Ltd [Member] | Put Option [Member]
Class Of Stock [Line Items]
Number of shares sold	2,103,169
Cash consideration received on transaction			$ 22.7