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Employee Benefit Plans (Narratives) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares outstanding for options and awards	3,218,000		2,719,000
Share-based compensation expense	$ 0	$ 0
Weighted-average grant-date fair value of options granted (in dollars per share)	$ 6.70
Awards granted	5,485,000
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting percentage	The RSUs vest from the original grant date as to one-third (1/3) on the one-year anniversary and one-twelfth (1/12) each quarter thereafter, subject to continued service to the Company
Employees and Directors \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Awards granted	5,484,772
Executive Officers and Directors \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Awards granted	566,038
Aerohive 2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares outstanding for options and awards	1,457,321
2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grant-date fair value of options granted (in dollars per share)	$ 2.02	$ 2.73
Shares issued under stock purchase plan	1,233,544	1,280,708