SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration of Risk (Details) - Canon Medical Systems Corporation - Customer Concentration Risk	12 Months Ended
Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Sales Revenue, Net
Concentration Risk [Line Items]
Concentration risk, percentage	17.30%	18.10%	19.30%
Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	10.10%	9.80%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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