Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Amount of stock repurchase plan authorized.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Common Stock Incentive, Stock Purchase Plans, and Other Compensation Plans - Narrative (Details) - USD ($)			1 Months Ended		12 Months Ended		25 Months Ended
	Dec. 07, 2017	Jun. 26, 2014	Dec. 31, 2016	Aug. 31, 2016	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2016	Dec. 16, 2014	Jun. 30, 2011	Jun. 30, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock options and warrants granted (in shares)						185,000
Aggregate intrinsic value of options exercisable					$ 29,000
Aggregate intrinsic value of options					29,000
Unrecognized compensation cost related to stock option and restricted awards					400,000
Common stock repurchased - value					7,000	$ 1,293,000
Amended Securities Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock repurchase - amount								$ 5,000,000
Share repurchases (in shares)							37,727
Common stock repurchased - value							$ 492,000
Common stock repurchased (in dollars per share)							$ 13.04
Amended Securities Repurchase Program \| Board Of Directors, Chief Executive Officer and Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share repurchases (in shares)				38,400
Common stock repurchased - value				$ 308,000
Common stock repurchased (in dollars per share)				$ 8.02
Amended Securities Repurchase Program \| Chief Operating Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share repurchases (in shares)			120,370
Common stock repurchased - value			$ 975,000
Common stock repurchased (in dollars per share)			$ 8.10
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized					$ 300,000	100,000
Unrecognized compensation cost over a weighted-average period					1 year 10 months 24 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized					$ 200,000	$ 1,000,000
Unrecognized compensation cost over a weighted-average period					1 year 2 months 12 days
Unrecognized expensed recognized					$ 100,000
Astrotech - The 2008 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares available for future issuance (in shares)					0					1,100,000
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)									350,000
Common stock options and warrants granted (in shares)	225,000	400,000
Common stock shares available for grant (in shares)					243,677