Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2018	Jul. 01, 2017
Cash flows from operating activities:
Net income (loss)	$ 38,796	$ (11,196)
Adjustments to reconcile net income (loss) to net cash provided (used) by operating activities:
Depreciation and amortization	65,303	64,187
Stock-based compensation	52,015	56,139
Other non-cash items, net	304	1,536
Changes in operating assets and liabilities, excluding the effects of acquisitions:
Accounts receivable	21,195	34,913
Accounts payable and accrued expenses	(16,539)	2,594
Accrued compensation and benefits	(22,348)	(50,518)
Deferred revenue	82,794	45,985
Accrued income taxes	(30,005)	(17,832)
Other current assets and prepaid expenses	(5,434)	(7,317)
Other noncurrent assets and liabilities	(759)	(16,028)
Net cash provided by operating activities	185,322	102,463
Cash flows from investing activities:
Additions to property and equipment	(18,666)	(19,333)
Purchase of intangible asset	(3,000)	0
Purchases of short- and long-term marketable securities	(18,063)	(14,173)
Proceeds from maturities of short- and long-term marketable securities	13,640	13,440
Acquisitions of businesses, net of cash acquired	(3,000)	(4,960)
Purchases of investments	(1,000)	0
Proceeds from sales of investments	0	15,218
Net cash used by investing activities	(30,089)	(9,808)
Cash flows from financing activities:
Borrowings under credit facility	200,000	150,000
Repayments of borrowings under credit facility	(220,000)	(190,000)
Repurchases of common stock	(100,000)	(34,994)
Proceeds from issuance of common stock	7,472	3,978
Credit facility origination costs	0	(184)
Contingent consideration	(7,750)	(11,054)
Payments of withholding taxes in connection with vesting of stock-based awards	(44,797)	(26,244)
Net cash used in financing activities	(165,075)	(108,498)
Effect of exchange rate changes on cash and cash equivalents	(3,609)	(1,397)
Net increase (decrease) in cash and cash equivalents	(13,451)	(17,240)
Cash and cash equivalents, beginning of period	280,003	277,935
Cash and cash equivalents, end of period	$ 266,552	$ 260,695