Stock Repurchase Activities (Parenthetical) (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Jan. 31, 2012
Share Repurchases [Line Items]
Settlement of equity forward contract	$ 33.3us-gaap_PaymentsForRepurchaseOfEquity
Common stock issued for settlement of equity forward contract	1,105,457

The cash outflow to reacquire common and preferred stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

Name:	us-gaap_PaymentsForRepurchaseOfEquity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration