Long-Term Debt - Narrative (Details)	Sep. 27, 2019 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Oct. 31, 2001 USD ($)
Line of Credit Facility [Line Items]
Revolving credit facility borrowings, outstanding amount		$ 1,200,000	$ 1,600,000
U.S. Revolver | Amended And Restated Credit Agreement
Line of Credit Facility [Line Items]
Revolving credit facility	$ 75,000,000
Revolving credit facility borrowings, outstanding amount		0
Amount of credit facility remaining borrowing capacity		61,600,000
Revolving credit facility, increase (up to)	50,000,000.0
Revolving credit facility, minimum of (or less)	$ 15,000,000
Debt covenant, consolidated leverage ratio (greater than)	3.0
Debt covenant, consolidated interest coverage ratio (less than)	3.0
Cash collateral pledged balance	$ 30,000,000
Restricted cash			$ 25,100,000
Cash collateral percent of outstanding debt (at least)	102.00%
Percentage of voting capital stock pledged as collateral	100.00%
Non-domestic subsidiaries of voting capital stock	65.00%
U.S. Revolver | Amended And Restated Credit Agreement | Federal Funds Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.50%
U.S. Revolver | Amended And Restated Credit Agreement | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
U.S. Revolver | Financial Standby Letter of Credit | Amended And Restated Credit Agreement
Line of Credit Facility [Line Items]
Guarantee liability		13,400,000
Industrial Development Revenue Bonds
Line of Credit Facility [Line Items]
Borrowings				$ 8,000,000
Reimbursement agreement requires annual redemptions		$ 400,000
Interest rate		1.69%
Minimum | U.S. Revolver | Amended And Restated Credit Agreement | Eurocurrency Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.25%
Minimum | U.S. Revolver | Amended And Restated Credit Agreement | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	(0.25%)
Maximum | U.S. Revolver | Amended And Restated Credit Agreement | Eurocurrency Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.75%
Maximum | U.S. Revolver | Amended And Restated Credit Agreement | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.25%