Income Taxes - Expense (Benefit) from Income Taxes (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Current	$ 0	$ 0	$ 0	$ 0
Deferred	0	0	0	0
Total Federal	0	0	0	0
Current	0	0	2	1
Deferred	0	0	0	0
Total State	0	0	2	1
Current	0	0	154	19
Deferred	0	0	0	0
Total Foreign	0	0	154	19
Total income tax expense	$ 0	$ 0	$ 156	$ 20	$ (5,100)