Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Cash flows from operating activities:
Net income (loss)	$ 253,434	$ (344,690)	$ 1,261,953
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Loss on extinguishment of debt	0	10,039	0
Loss on fair value of debt conversion liability	0	12,070	0
Depreciation of equipment, building, furniture and fixtures, and amortization of leasehold improvements	87,576	84,214	77,189
Share-based compensation costs	59,736	52,972	48,360
Amortization of intangible assets	35,136	25,806	45,713
Deferred taxes	19,865	463,631	(1,126,732)
Provision for doubtful accounts	6,740	2,700	18,221
Provision for inventory excess and obsolescence	28,085	30,615	35,459
Provision for warranty	23,105	20,992	7,965
Other	(910)	21,685	22,417
Changes in assets and liabilities:
Accounts receivable	65,712	(168,357)	(66,123)
Inventories	(112,941)	(27,445)	(91,567)
Prepaid expenses and other	(96,618)	(21,425)	(33,834)
Accounts payable, accruals and other obligations	27,740	85,798	33,897
Deferred revenue	16,480	(19,344)	1,964
Net cash provided by operating activities	413,140	229,261	234,882
Cash flows used in investing activities:
Payments for equipment, furniture, fixtures and intellectual property	(62,579)	(67,616)	(94,600)
Purchase of available for sale securities	(158,074)	(286,824)	(299,038)
Proceeds from maturities of available for sale securities	248,748	410,109	335,075
Purchase of equity investment	(2,667)	(1,767)	0
Settlement of foreign currency forward contracts, net	(1,351)	9,385	(2,810)
Acquisition of businesses, net of cash acquired	0	(82,670)	0
Net cash used in investing activities	24,077	(19,383)	(61,373)
Cash flows from financing activities:
Proceeds from issuance of long-term debt, net	0	305,125	0
Payment of long-term debt	(7,000)	(292,730)	(233,554)
Payment for debt conversion liability	(111,268)	0	0
Payment for make-whole provision upon conversion of long-term debt	0	(13,453)	0
Payment for modification of term loans	0	0	(93,625)
Payment of debt issuance costs	(1,191)	(1,936)	(722)
Payment of capital lease obligations	(3,319)	(3,624)	(3,562)
Shares repurchased for tax withholdings on vesting of restricted stock units	(29,059)	(4,757)	0
Repurchases of common stock - repurchase program	(150,076)	(110,981)	0
Proceeds from issuance of common stock	22,947	23,127	20,412
Net cash used in financing activities	(278,966)	(99,229)	(311,051)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	476	(5,856)	494
Net increase (decrease) in cash, cash equivalents and restricted cash	158,727	104,793	(137,048)
Cash, cash equivalents and restricted cash at beginning of fiscal year	745,434	640,641	777,689
Cash, cash equivalents and restricted cash at end of fiscal year	904,161	745,434	640,641
Supplemental disclosure of cash flow information
Cash paid during the fiscal year for interest	39,579	44,750	47,235
Cash paid during the fiscal year for income taxes, net	33,570	26,900	22,136
Non-cash investing and financing activities
Purchase of equipment in accounts payable	16,549	5,118	6,214
Equipment acquired under and building subject to capital lease	0	0	50,370
Contingent consideration for acquisition of business	0	10,900	0
3.75% Convertible Senior Notes due October 15, 2018
Non-cash investing and financing activities
Conversion of convertible senior notes	0	61,270	0
4.0% Convertible Senior Notes due March 15, 2015
Non-cash investing and financing activities
Conversion of convertible senior notes	0	214,286	0
3.75% Convertible Senior Notes due October 15, 2018 (New)
Non-cash investing and financing activities
Conversion of convertible senior notes	$ 52,944	$ 0	$ 0