COMMITMENTS AND CONTINGENCIES - Additional Information (Details) $ in Thousands			1 Months Ended	3 Months Ended
	Mar. 12, 2018 plaintiff	Nov. 24, 2016 patent	Oct. 31, 2015 installment	Sep. 29, 2018 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)
Contingencies And Commitments [Line Items]
Capital lease term			5 years
Early buyout of capital leases				$ 1,780	$ 168
Number of capital lease installment payments | installment			20
Interest rate on capital lease (percent)			1.15%
Malaysian goods and services tax refund claim				2,500
Number of allegedly infringed patents included in third party lawsuit which may incorporate Oclaro components | patent		7
Prepaid Expenses and Other Current Assets
Contingencies And Commitments [Line Items]
Malaysian goods and services tax refund claim				700
Inventory in Excess of Future Demand Forecasts | Accrued Expenses and Other Liabilities
Contingencies And Commitments [Line Items]
Purchase commitments				$ 3,100		$ 6,300
Minimum
Contingencies And Commitments [Line Items]
Warranty for products from date of sale				12 months
Capital lease term				1 year
Maximum
Contingencies And Commitments [Line Items]
Warranty for products from date of sale				36 months
Capital lease term				5 years
Japan
Contingencies And Commitments [Line Items]
Early buyout of capital leases				$ 2,000
Shareholder Lawsuits
Contingencies And Commitments [Line Items]
Number of plaintiffs | plaintiff	7