Auction Rate Securities - Significant Assumptions Used to Determine Fair Value of Auction Rate Securities (Details)	12 Months Ended
	Oct. 31, 2018	Oct. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Discount rates	0.37%
Libor plus stated yield	2.00%	2.00%
Yields		2.15%
Average expected lives	4 years
Minimum
Schedule of Available-for-sale Securities [Line Items]
Discount rates		0.42%
Average expected lives		4 years
Maximum
Schedule of Available-for-sale Securities [Line Items]
Discount rates		0.79%
Average expected lives		10 years