Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017
Significant Accounting Policies [Line Items]
Highly liquid investments, original maturity period	3 months
Unmarketable inventory value	$ 0.0
Operating loss carry forwards for state income tax			$ 186.0
Operating loss carry forwards for federal income tax			$ 371.1
Liability for uncertain tax positions	$ 0.0
Common stock equivalents excluded from the diluted per share calculation	25,685,221	26,762,930
Minimum
Significant Accounting Policies [Line Items]
Net operating loss carry forwards expiration year	2018
Maximum
Significant Accounting Policies [Line Items]
Net operating loss carry forwards expiration year	2037