Borrowings - Borrowings obligation table (Details) - USD ($) $ in Thousands	3 Months Ended
Jan. 01, 2022	Oct. 02, 2021	Sep. 29, 2018
Short-term Debt [Line Items]
Total short-term borrowings and current portion of long-term obligations	$ 9,005	$ 18,395
Interest rate For 1.3% Term loan due 2024	1.30%
Interest rate of state of Connecticut	1.00%
Euro term loan
Short-term Debt [Line Items]
Debt issuance cost for long term portion of the euro term loan	$ 2,300	3,000
Debt Issuance Costs, Gross			$ 500
Euro term loan
Short-term Debt [Line Items]
Debt issuance cost for short term euro term loan	2,700	2,800
Short-term Debt
Short-term Debt [Line Items]
Euro Term Loan due 2024	4,872	4,972
1.3% Term loan due 2024	1,416	1,448
1.0% State of Connecticut term loan due 2023	387	386
Line of credit borrowings	0	10,000
Facility construction loan in Germany due 2030	2,330	1,589
Total short-term borrowings and current portion of long-term obligations	9,005	18,395
Long-term Debt
Short-term Debt [Line Items]
Euro Term Loan due 2024	386,309	396,429
1.3% Term loan due 2024	2,477	2,896
1.0% State of Connecticut term loan due 2023	163	260
Facility construction loan in Germany due 2030 -LT	24,850	26,215
Long-term Debt	$ 413,799	$ 425,800

1.0% State of Connecticut Term Loan due 2023

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1.3% Term Loan due 2024

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Debt issuance cost for long term portion of the Euro term loan

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Debt issuance cost for short term portion of the Euro term loan

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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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