Stock-Based Compensation - Schedule of Weighted-Average Fair Value and the Assumptions Used to Measure Fair Value (Details) - $ / shares	3 Months Ended		9 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value (usd per share)			$ 13	$ 47
Expected volatility (percent)			32.50%	33.60%
Risk-free interest rate (percent)			1.20%	1.00%
Expected performance period in years			2 years 10 months 24 days	2 years 10 months 24 days
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value (usd per share)	$ 2	$ 6	$ 4	$ 8
Expected volatility (percent)	31.60%	26.70%	36.20%	26.30%
Risk-free interest rate (percent)	1.30%	1.60%	1.80%	1.70%
Expected dividend yield (percent)	4.30%	2.30%	3.50%	1.80%
Expected term in years	5 years 6 months	5 years 2 months 12 days	6 years	5 years 9 months 18 days