Related Party Transactions (Details) (USD $)	3 Months Ended		6 Months Ended
	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2014	Apr. 30, 2013	Oct. 31, 2013
Sponsored Funds [Abstract]
Investment advisory and administrative fees	$ 219,650,000	$ 201,790,000	$ 444,896,000	$ 393,982,000
Distribution fees	19,058,000	19,845,000	38,867,000	39,918,000
Service fees	30,829,000	31,132,000	63,120,000	62,262,000
Shareholder services fees	634,000	548,000	1,239,000	1,088,000
Other revenue	352,000	268,000	732,000	403,000
Total	270,523,000	253,583,000	548,854,000	497,653,000
Investment advisory fees waived by the Company	2,800,000	1,600,000	5,500,000	4,400,000
Proceeds from sales	48,307,000	18,474,000	63,851,000	39,290,000
Net realized gains (losses)	(399,000)	342,000	(336,000)	5,251,000
Related party expenses	5,000,000	5,600,000	10,300,000	10,700,000
Related party accounts receivable	92,800,000		92,800,000		94,000,000
Employee Loan Program
Maximum loan amount available under the plan	$ 20,000,000		$ 20,000,000