Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Cash flows from operating activities:
Net loss	$ (10,245)	$ (29,065)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	42,683	42,904
Stock-based compensation	39,565	38,025
Excess tax benefits from stock-based awards	(139)	(56)
Non-cash portion of restructuring charges	260	0
Other non-cash items, net	479	204
Changes in operating assets and liabilities, excluding the effects of acquisitions:
Accounts receivable	15,373	63,617
Accounts payable, accrued expenses and other current liabilities	11,183	(25,907)
Accrued compensation and benefits	(51,769)	8,215
Deferred revenue	27,457	24,019
Accrued and deferred income taxes	(14,680)	(8,826)
Other current assets and prepaid expenses	(11,424)	(1,882)
Other noncurrent assets and liabilities	(20,332)	(1,109)
Net cash provided by operating activities	28,411	110,139
Cash flows from investing activities:
Additions to property and equipment	(14,789)	(8,866)
Purchases of short- and long-term marketable securities	(3,420)	0
Proceeds from sales and maturities of short- and long-term marketable securities	4,700	0
Acquisitions of businesses, net of cash acquired	0	(164,191)
Proceeds from sales of investments	15,218	0
Net cash provided by (used in) investing activities	1,709	(173,057)
Cash flows from financing activities:
Borrowings	100,000	170,000
Repayments of borrowings under credit facility	(140,000)	0
Proceeds from issuance of common stock	3,978	1
Excess tax benefits from stock-based awards	139	56
Credit facility origination costs	(184)	(1,050)
Contingent consideration	(2,711)	(1,250)
Payments of withholding taxes in connection with vesting of stock-based awards	(19,166)	(15,471)
Net cash provided by (used in) financing activities	(57,944)	152,286
Effect of exchange rate changes on cash and cash equivalents	(6,795)	5,671
Net increase (decrease) in cash and cash equivalents	(34,619)	95,039
Cash and cash equivalents, beginning of period	277,935	273,417
Cash and cash equivalents, end of period	$ 243,316	$ 368,456