Income Taxes - Summary (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Oct. 02, 2016
Income before income taxes:
United States	$ 180,034	$ 166,074	$ 113,576
Foreign	(5,472)	5,687	10,890
Total income before income taxes	174,562	171,761	124,466
Current:
Federal	46,840	45,604	22,277
State	9,228	8,860	5,634
Foreign	10,897	9,337	6,651
Total current income tax expense	66,965	63,801	34,562
Deferred:
Federal	(22,072)	(4,251)	6,231
State	(1,471)	(945)	(16)
Foreign	(5,817)	(4,761)	(164)
Total deferred income tax expense	(29,360)	(9,957)	6,051
Total income tax expense	$ 37,605	$ 53,844	$ 40,613
Reconciliation of effective income tax rate
Tax at federal statutory rate	24.50%	35.00%	35.00%
State taxes, net of federal benefit	4.20%	3.40%	3.10%
Research and Development (R&D) credit	(1.40%)	(1.80%)	(3.40%)
Domestic production deduction	(0.20%)	(0.70%)	(0.70%)
Tax differential on foreign earnings	0.50%	0.00%	(1.60%)
Non-taxable foreign interest income	(2.00%)	(2.90%)	(3.90%)
Non-deductible executive compensation	0.00%	0.00%	2.00%
Goodwill	1.70%	0.00%	0.00%
Stock compensation	(2.70%)	(2.80%)	0.30%
Valuation allowance	(0.50%)	(0.50%)	2.40%
Change in uncertain tax positions	1.90%	1.80%	(2.00%)
Revaluation of deferred taxes	(8.40%)	0.00%	0.00%
Deferred tax adjustments	2.10%	0.00%	0.00%
Other	1.80%	(0.20%)	1.40%
Total income tax expense	21.50%	31.30%	32.60%