Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2021	Mar. 28, 2020
Cash flows from operating activities:
Net income	$ 132,777	$ 42,611
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	40,169	40,193
Amortization of right-of-use lease assets	18,956	19,143
Stock-based compensation	90,828	48,420
Other non-cash items, net	(720)	(1,695)
Changes in operating assets and liabilities, excluding the effects of acquisitions:
Accounts receivable	(9,854)	20,187
Accounts payable and accrued expenses	6,142	6,583
Accrued compensation and benefits	(7,038)	(4,629)
Deferred revenue	52,210	17,393
Accrued income taxes	(4,944)	(43,815)
Other current assets and prepaid expenses	(17,049)	681
Operating lease liabilities	(9,982)	(671)
Other noncurrent assets and liabilities	(56,041)	(49,072)
Net cash provided by operating activities	235,454	95,329
Cash flows from investing activities:
Additions to property and equipment	(8,242)	(10,243)
Purchases of short- and long-term marketable securities	(7,562)	(10,151)
Proceeds from sales of short- and long-term marketable securities	56,170	0
Proceeds from maturities of short- and long-term marketable securities	9,861	9,971
Acquisitions of businesses, net of cash acquired	(717,198)	(468,520)
Other investing activities	(3,353)	2,200
Net cash used in investing activities	(670,324)	(476,743)
Cash flows from financing activities:
Proceeds from issuance of Senior Notes	0	1,000,000
Borrowings under credit facility	600,000	455,000
Repayments of borrowings under credit facility	(98,000)	(480,000)
Proceeds from issuance of common stock	10,484	8,980
Debt issuance costs	0	(16,266)
Payments of withholding taxes in connection with stock-based awards	(27,242)	(23,571)
Payments of principal for financing leases	(279)	0
Net cash provided by financing activities	484,963	944,143
Effect of exchange rate changes on cash, cash equivalents and restricted cash	543	(5,740)
Net change in cash, cash equivalents, and restricted cash	50,636	556,989
Cash, cash equivalents, and restricted cash, beginning of period	275,960	270,689
Cash, cash equivalents, and restricted cash, end of period	$ 326,596	$ 827,678