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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, 2021	Jun. 30, 2020	May 26, 2021	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	1
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense recognized	$ 1	$ 147
Unrecognized compensation cost over a weighted-average period	1 year 3 months 18 days
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense recognized	$ 625	$ 202
Unrecognized compensation cost over a weighted-average period	2 years 8 months 12 days
Unrecognized compensation cost recognized	$ 3,700
2021 Omnibus Equity Plan \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares initially available for grant (in shares)			1,500,000
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