Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Jun. 30, 2018
Condensed Consolidated Balance Sheets [Abstract]
Property, plant and equipment, accumulated depreciation	$ 131,212	$ 126,026
Common stock, shares authorized	200,000,000	200,000,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares issued	56,815,925	56,685,925
Common stock, shares outstanding	56,815,925	56,685,925
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares issued
Preferred stock, shares outstanding
Treasury shares, shares outstanding	24,891,292	24,891,292

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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