CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Total AOS Shareholders' Equity	Common Shares	Treasury Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	$ 443,289
Beginning balance at Jun. 30, 2019		$ 291,024	$ 62	$ (66,240)	$ 234,410	$ (2,693)	$ 125,485
Beginning balance, noncontrolling interest at Jun. 30, 2019								$ 152,265
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	437,553
Reissuance of treasury stock upon exercise of common stock options and release of restricted stock units	0	0		13			(13)
Withholding tax on restricted stock units	(96)	(96)			(96)
Share-based compensation	2,369	2,369			2,369
Net loss	1,009	1,009					1,009
Net loss attributable to noncontrolling interest	(2,867)							(2,867)
Net loss including noncontrolling interest	(1,858)
Cumulative translation adjustment		(3,183)				(3,183)
Cumulative translation adjustment, attributable to noncontrolling interest								(2,968)
Cumulative translation adjustment, including portion attributable to noncontrolling interest	(6,151)
Ending balance at Sep. 30, 2019		291,123	62	(66,227)	236,683	(5,876)	126,481
Ending balance, noncontrolling interest at Sep. 30, 2019								146,430
Ending balance, including portion attributable to noncontrolling interest at Sep. 30, 2019	437,553
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	437,553
Beginning balance, including portion attributable to noncontrolling interest	431,888
Beginning balance at Jun. 30, 2020	293,689	293,689	64	(66,184)	246,103	(5,127)	118,833
Beginning balance, noncontrolling interest at Jun. 30, 2020	138,199							138,199
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	449,222
Reissuance of treasury stock upon exercise of common stock options and release of restricted stock units	0	0		13			(13)
Withholding tax on restricted stock units	(412)	(412)			(412)
Share-based compensation	2,276	2,276			2,276
Restricted stock units settlement in connection with service	1,000	1,000			1,000
Net loss	9,574	9,574					9,574
Net loss attributable to noncontrolling interest	(807)							(807)
Net loss including noncontrolling interest	8,767
Cumulative translation adjustment		2,981				2,981
Cumulative translation adjustment, attributable to noncontrolling interest								2,722
Cumulative translation adjustment, including portion attributable to noncontrolling interest	5,703
Ending balance at Sep. 30, 2020	309,108	$ 309,108	$ 64	$ (66,171)	$ 248,967	$ (2,146)	$ 128,394
Ending balance, noncontrolling interest at Sep. 30, 2020	140,114							$ 140,114
Ending balance, including portion attributable to noncontrolling interest at Sep. 30, 2020	449,222
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	$ 449,222