Related Party Transactions (Details) (USD $)	12 Months Ended
	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2010
Sponsored Funds [Abstract]
Investment advisory and administrative fees	$ 744,351,000	$ 768,430,000	$ 669,017,000
Distribution fees	80,920,000	92,770,000	91,750,000
Service fees	126,345,000	144,530,000	139,741,000
Shareholder services fees	2,411,000	2,188,000	2,255,000
Total	954,027,000	1,007,918,000	902,763,000
Investment advisory fees waived by the Company	8,800,000	13,000,000	18,000,000
Proceeds from sales	60,726,000	61,866,000	32,586,000
Net realized (losses) gains	(92,000)	586,000	3,048,000
Related party expenses	18,900,000	16,000,000	16,000,000
Related party accounts receivable	84,400,000	82,500,000
Employee Loan Program
Maximum loan amount available under the plan	$ 10,000,000
Minimum fixed borrowing rate under the plan	0.90%
Maximum fixed borrowing rate under the plan	5.00%