Stock-Based Compensation (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014
Stock-Based Compensation
Stock-based compensation expense	$ 129	$ 130	$ 316	$ 300
Income tax benefit	(42)	(43)	(102)	(96)
Stock-based compensation expense, net of tax	87	87	214	204
Restricted Stock Awards
Shares
Outstanding at beginning of period (in shares)			40,808,000
Granted (in shares)			15,722,000
Vested (in shares)			(16,325,000)
Forfeited (in shares)			(1,540,000)
Outstanding at end of period (in shares)	38,665,000		38,665,000
Weighted-Average Grant Date Fair Value Per Share
Outstanding at beginning of period (in dollars per share)			$ 24
Granted (in dollars per share)			$ 37
Vested (in dollars per share)			$ 24
Forfeited (in dollars per share)			$ 26
Outstanding at end of period (in dollars per share)	$ 30		$ 30
Unrecognized pre-tax stock-based compensation expense and recognition period
Unrecognized pre-tax stock-based compensation expense	746		746
Remaining weighted-average vesting period over which pre-tax stock-based compensation expense is expected to be recognized			1 year 6 months
Stock Options
Unrecognized pre-tax stock-based compensation expense and recognition period
Unrecognized pre-tax stock-based compensation expense	77		77
Remaining weighted-average vesting period over which pre-tax stock-based compensation expense is expected to be recognized			1 year 10 months 24 days
Weighted-average fair value and the assumptions used to measure fair value
Weighted- average fair value of grants per option (in dollars per share)	$ 6.77	$ 7.03	$ 7.98	$ 7.43
Expected volatility (as a percent)	27.70%	30.40%	26.30%	33.50%
Risk-free interest rate (as a percent)	1.40%	1.60%	1.70%	1.80%
Expected dividend yield (as a percent)	2.20%	2.10%	1.70%	2.20%
Expected term in years	5 years 2 months 12 days	5 years 2 months 12 days	5 years 9 months 18 days	5 years 8 months 12 days
Shares
Outstanding at beginning of period (in shares)			57,853,000
Granted and assumed through acquisition (in shares)			8,081,000
Exercised (in shares)			(9,213,000)
Forfeited/cancelled/expired (in shares)			(15,281,000)
Outstanding at end of period (in shares)	41,440,000		41,440,000
Vested and expected to vest at end of period (in shares)	38,683,000		38,683,000
Exercisable at end of period (in shares)	18,702,000		18,702,000
Weighted-Average Exercise Price
Outstanding at beginning of period (in dollars per share)			$ 27
Granted and assumed through acquisition (in dollars per share)			$ 37
Exercised (in dollars per share)			$ 19
Forfeited/cancelled/expired (in dollars per share)			$ 41
Outstanding at end of period (in dollars per share)	$ 26		$ 26
Vested and expected to vest at end of period (in dollars per share)	$ 26		$ 26
Exercisable at end of period (in dollars per share)	$ 25		$ 25
Weighted-Average Remaining Contractual Term
Outstanding at end of period			5 years 6 months
Vested and expected to vest at end of period			5 years 6 months
Exercisable at end of period			4 years 3 months 18 days
Aggregate Intrinsic Value
Outstanding at end of period	371		371
Vested and expected to vest at end of period	349		349
Exercisable at end of period	191		191
Options exercised	$ 35		$ 169