Income Taxes - Reconciliation of unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Oct. 01, 2017	Oct. 02, 2016
Reconciliation of unrecognized tax benefits [Roll Forward]
Beginning balance	$ 9,337	$ 22,786	$ 21,618
Additions for current year tax positions	1,108	1,060	2,802
Additions for prior year tax positions	3,478	2,365	1,466
Reductions for prior year tax positions	0	(6,875)	(3,100)
Settlements	(4,496)	(9,999)	0
Ending balance	$ 9,427	$ 9,337	$ 22,786

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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