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Common Stock Incentive, Stock Purchase Plans, and Other Compensation Plans - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 29, 2020	Dec. 07, 2018	Dec. 07, 2017	Jun. 26, 2014	Jun. 30, 2011
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value of options exercisable	$ 0
Aggregate intrinsic value of options	0
Unrecognized compensation cost related to stock option and restricted awards	13
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense recognized	$ 147	$ 171
Unrecognized compensation cost over a weighted-average period	2 years 3 months 18 days
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense recognized	$ 202	$ 135
Unrecognized compensation cost over a weighted-average period	1 year 6 months
Unrecognized compensation cost recognized	$ 295
Astrotech - The 2011 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for future issuance (in shares)			1,500,000	537,197	225,000	400,000	350,000
Common stock shares available for grant (in shares)	2,122,523