Schedule I - Condensed Unconsolidated Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Condensed Financial Statements, Captions [Line Items]
Cost of revenue	$ 335,542	$ 309,625	$ 291,516
Gross profit	115,378	111,928	91,821
Operating expenses:
Selling, general and administrative	75,967	66,164	48,842
Total operating expenses	122,398	103,508	78,677
Operating loss	(7,020)	8,420	13,144
Interest expense	(6,905)	(821)	(91)
Net income (loss) including noncontrolling interest	(14,638)	4,948	9,260
Net loss attributable to noncontrolling interest	(16,499)	(9,315)	(4,569)
Net income attributable to Alpha and Omega Semiconductor Limited	1,861	14,263	13,829
Parent Company
Condensed Financial Statements, Captions [Line Items]
Revenue	4,292	4,096	3,772
Cost of revenue	0	0	0
Gross profit	4,292	4,096	3,772
Operating expenses:
Selling, general and administrative	4,599	4,479	3,938
Total operating expenses	4,599	4,479	3,938
Operating loss	(307)	(383)	(166)
Interest income	3	7	20
Income (loss) on equity investment in subsidiaries	(14,334)	5,324	9,406
Net income (loss) including noncontrolling interest	(14,638)	4,948	9,260
Net loss attributable to noncontrolling interest	(16,499)	(9,315)	(4,569)
Net income attributable to Alpha and Omega Semiconductor Limited	$ 1,861	$ 14,263	$ 13,829