Financing (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016	Oct. 01, 2016
Line of Credit Facility [Line Items]
Percent added to Adjusted LIBOR rate for one month interest period			1.00%
Commitment fees incurred on credit facility	$ 106,000	$ 48,000	$ 320,000	$ 170,000
Annual excess cash flow percentage per credit agreement			50.00%
Net cash proceed percentage per credit agreement			100.00%
Long-term debt	$ 480,753,000		$ 480,753,000		$ 493,545,000
Alternate base rate
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	3.25%		3.25%
Minimum
Line of Credit Facility [Line Items]
Line of credit facility, commitment fees payable, percent			0.25%
Minimum | Alternate base rate
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	1.75%		1.75%
Maximum
Line of Credit Facility [Line Items]
Line of credit facility, commitment fees payable, percent			0.50%
Revolving credit facility
Line of Credit Facility [Line Items]
Line of credit facility, borrowing capacity					120,000,000
Maximum borrowing capacity					120,000,000
Short-term borrowings	$ 0		$ 0
Letters of credit outstanding, amount	37,673,000		37,673,000
Line of credit facility, remaining borrowing capacity	$ 82,327,000		$ 82,327,000
Revolving credit facility | London interbank offered rate (LIBOR)
Line of Credit Facility [Line Items]
Debt interest rate spread			0.50%
Term loan B facility
Line of Credit Facility [Line Items]
Line of credit facility, borrowing capacity					460,000,000
Principal amount, amortization percentage	1.00%		1.00%
Weighted average interest rate	5.10%		5.10%
Long-term debt	$ 458,239,000		$ 458,239,000		465,465,000
Term loan B facility | London interbank offered rate (LIBOR)
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	1.23%		1.23%
Term loan B facility | Alternate base rate
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	4.25%		4.25%
Eurocurrency borrowing | London interbank offered rate (LIBOR)
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	4.00%		4.00%
Eurocurrency term loans | London interbank offered rate (LIBOR)
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	4.25%		4.25%
Eurocurrency term loans | Minimum | London interbank offered rate (LIBOR)
Line of Credit Facility [Line Items]
Effective interest rate applicable to outstanding credit facility (in hundredths)	0.75%		0.75%
Tangible equity units senior amortizing note
Line of Credit Facility [Line Items]
Long-term debt	$ 22,514,000		$ 22,514,000		$ 28,080,000