Unaudited Condensed Consolidated Statements of Stockholders' Equity Statement - USD ($) shares in Thousands, $ in Thousands	Total		Cumulative Effect, Period of Adoption, Adjustment	[1]	Common Stock	Capital in Excess of Par Value	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	[1]	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Total  Synopsys Stockholders’ Equity	Total  Synopsys Stockholders’ Equity Cumulative Effect, Period of Adoption, Adjustment	Non-controlling Interest
Balance (in shares) at Oct. 31, 2020					152,618
Beginning balance at Oct. 31, 2020	$ 4,912,367				$ 1,528	$ 1,653,166	$ 3,795,397			$ (488,613)	$ (54,074)	$ 4,907,404		$ 4,963
Beginning balance (Retained earnings adjustment due to adoption of ASC 326) at Oct. 31, 2020			$ (3,200)					$ (3,200)					$ (3,200)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	356,830						357,423					357,423		(593)
Other comprehensive income (loss), net of tax effects	$ 12,719										12,719	12,719
Purchases of treasury stock (in shares)	(1,593)				(1,593)
Purchases of treasury stock	$ (398,082)				$ (16)	16				(398,082)		(398,082)
Common stock issued, net of shares withheld for employee taxes (in shares)	1,529				1,529
Common stock issued, net of shares withheld for employee taxes	$ 48,503				$ 14	(136,749)				185,238		48,503
Stock-based compensation	163,368					163,368						163,368
Balance (in shares) at Apr. 30, 2021					152,554
Ending balance at Apr. 30, 2021	5,092,505				$ 1,526	1,679,801	4,149,620			(701,457)	(41,355)	5,088,135		4,370
Balance (in shares) at Jan. 31, 2021					152,364
Beginning balance at Jan. 31, 2021	4,886,898				$ 1,526	1,589,175	3,954,542			(628,216)	(34,775)	4,882,252		4,646
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	194,802						195,078					195,078		(276)
Other comprehensive income (loss), net of tax effects	$ (6,580)										(6,580)	(6,580)
Purchases of treasury stock (in shares)	(756)				(756)
Purchases of treasury stock	$ (195,211)				$ (8)	8				(195,211)		(195,211)
Equity forward contract, net	$ 50,000					50,000						50,000
Common stock issued, net of shares withheld for employee taxes (in shares)	946				946
Common stock issued, net of shares withheld for employee taxes	$ 83,010				$ 8	(38,968)				121,970		83,010
Stock-based compensation	79,586					79,586						79,586
Balance (in shares) at Apr. 30, 2021					152,554
Ending balance at Apr. 30, 2021	5,092,505				$ 1,526	1,679,801	4,149,620			(701,457)	(41,355)	5,088,135		4,370
Balance (in shares) at Oct. 31, 2021					153,062
Beginning balance at Oct. 31, 2021	5,298,943				$ 1,531	1,576,363	4,549,713			(782,866)	(49,604)	5,295,137		3,806
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	607,781						608,468					608,468		(687)
Other comprehensive income (loss), net of tax effects	$ (63,495)										(63,495)	(63,495)
Purchases of treasury stock (in shares)	(1,685)				(1,685)
Purchases of treasury stock	$ (535,000)				$ (16)	16				(535,000)		(535,000)
Equity forward contract, net	$ 35,000					35,000						35,000
Common stock issued, net of shares withheld for employee taxes (in shares)	1,578				1,578
Common stock issued, net of shares withheld for employee taxes	$ 18,917				$ 15	(299,730)				318,632		18,917
Stock-based compensation	205,832					205,832						205,832
Adjustments to redeemable non-controlling interest	(548)						(548)					(548)
Balance (in shares) at Apr. 30, 2022					152,955
Ending balance at Apr. 30, 2022	5,567,430				$ 1,530	1,517,481	5,157,633			(999,234)	(113,099)	5,564,311		3,119
Balance (in shares) at Jan. 31, 2022					153,256
Beginning balance at Jan. 31, 2022	5,390,233				$ 1,533	1,430,226	4,863,400			(856,929)	(51,457)	5,386,773		3,460
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	294,440						294,781					294,781		(341)
Other comprehensive income (loss), net of tax effects	$ (61,642)										(61,642)	(61,642)
Purchases of treasury stock (in shares)	(984)	[2]			(984)
Purchases of treasury stock	$ (290,000)	[2]			$ (9)	9				(290,000)		(290,000)
Equity forward contract, net	$ 40,000					40,000						40,000
Common stock issued, net of shares withheld for employee taxes (in shares)	683	[2]			683
Common stock issued, net of shares withheld for employee taxes	$ 84,886				$ 6	(62,815)				147,695		84,886
Stock-based compensation	110,061					110,061						110,061
Adjustments to redeemable non-controlling interest	(548)						(548)					(548)
Balance (in shares) at Apr. 30, 2022					152,955
Ending balance at Apr. 30, 2022	$ 5,567,430				$ 1,530	$ 1,517,481	$ 5,157,633			$ (999,234)	$ (113,099)	$ 5,564,311		$ 3,119

[1] At the beginning of fiscal 2021, we adopted the Accounting Standards Codification (ASC) 326, Measurement of Credit Losses on Financial Instruments, issued by the Financial Accounting Standards Board (FASB). ASC 326 replaced the incurred loss methodology with an expected loss methodology.

[2] Included the 161,215 shares and $40.0 million equity forward contract from the December 2021 ASR settled in February 2022.