Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Schedule Of Income Taxes [Line Items]
State net operating carry forwards	$ 35,400,000
Research and development credit carry forwards	5,289,000	$ 4,659,000
Net operating loss carryforwards	74,751,000	71,671,000
Net change in valuation allowance	2,300,000	$ 4,500,000	$ 914,000
Unrecognized deferred tax liabilities	$ 12,200,000
Minimum
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards expiration year	2019
Tax credit carryforward expiration year	2016
Maximum
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards expiration year	2035
Tax credit carryforward expiration year	2035
Federal
Schedule Of Income Taxes [Line Items]
Federal net operating carry forwards	$ 215,800,000
Federal Research And Development Credits
Schedule Of Income Taxes [Line Items]
Research and development credit carry forwards	2,700,000
California
Schedule Of Income Taxes [Line Items]
Research and development credit carry forwards	4,000,000
U K Operating Credits
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards	$ 4,700,000