Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, shares in Thousands, $ in Millions	9 Months Ended
	Jul. 31, 2017 USD ($) $ / shares shares
Shares
Outstanding at beginning of period (in shares) | shares	57,498
Granted and assumed through acquisition (in shares) | shares	5,267
Additional shares granted due to conversion (in shares) | shares	12,574
Exercised (in shares) | shares	(22,861)
Forfeited/canceled/expired (in shares) | shares	(8,475)
Outstanding at end of period (in shares) | shares	44,003
Vested and expected to vest at end of period (in shares) | shares	43,013
Exercisable at end of period (in shares) | shares	21,965
Weighted- Average Exercise Price
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 15
Granted and assumed through acquisition (in dollars per share) | $ / shares	24
Additional shares granted due to conversion (in dollars per share) | $ / shares	12
Exercised (in dollars per share) | $ / shares	13
Forfeited/canceled/expired (in dollars per share) | $ / shares	16
Outstanding at end of period (in dollars per share) | $ / shares	12
Vested and expected to vest at end of period (in dollars per share) | $ / shares	12
Exercisable at end of period (in dollars per share) | $ / shares	$ 11
Weighted- Average Remaining Contractual Term
Outstanding at end of period (term)	5 years
Vested and expected to vest at end of period (term)	4 years 10 months 24 days
Exercisable at end of period (term)	3 years 6 months
Aggregate Intrinsic Value
Outstanding at end of period | $	$ 237
Vested and expected to vest at end of period | $	233
Exercisable at end of period | $	$ 148
Number of stock options related to former ES segment (in shares) | shares	8,000
Weighted-average exercise price (in dollars per share) | $ / shares	$ 16