v2.4.0.6

Stock Repurchase Program - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified | 1 Months Ended | 12 Months Ended | 3 Months Ended |  |
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May 25, 2011 | Oct. 31, 2012 | Oct. 31, 2011 | Oct. 31, 2010 | Apr. 30, 2012 Accelerated Share Repurchase Agreement | Jan. 31, 2012 Accelerated Share Repurchase Agreement | Oct. 31, 2011 Accelerated Share Repurchase Agreement | Jan. 06, 2012 Accelerated Share Repurchase Agreement | Sep. 30, 2011 Accelerated Share Repurchase Agreement
Stock Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |
Stock repurchase program authorized amount | $ 500.0 | $ 500.0 |  |  |  |  |  |  |
Stock repurchase program remaining authorized repurchase amount |  | 272.4 |  |  |  |  |  |  |
Accelerated share repurchase agreement amount |  |  |  |  |  |  |  | 40.0 | 75.0
Stock repurchase program prepayment |  |  |  |  |  |  |  |  | 75.0
Initial number of shares received from accelerated share repurchase agreements |  |  |  |  |  |  | 1,710,376 |  |
Initial share value |  |  |  |  |  |  | 41.7 |  |
Remaining balance of value or shares to be settled |  |  |  |  |  |  | $ 33.3 |  |
Number of shares to settle equity forward contract |  |  |  |  | 1,368,616 | 1,105,457 |  |  |
Average purchase price per share |  | $ 29.64 | $ 26.53 | $ 22.43 | $ 29.23 | $ 26.64 |  |  |

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- Definition Accelerated share repurchase agreement amount. + References No definition available. + Details
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- Definition Accelerated share repurchase initial share delivery amount. + References No definition available. + Details
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- Definition Accelerated Share Repurchases Settlement Of Equity Forward. + References No definition available. + Details
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- Details
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- Definition Stock repurchase program prepayment. + References No definition available. + Details
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- Definition Amount of cash payment to or cash receipt from the bank; or the stock issuance to or stock received from the bank in the settlement of the accelerated share repurchase agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 99-7 -Paragraph 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Section B -Paragraph 11A -Chapter 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 + Details
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- Definition The amount authorized by an entity's Board of Directors under a stock repurchase plan. + References No definition available. + Details
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- Definition The remaining repurchase amount authorized by an entity's Board of Directors under a stock repurchase plan. + References No definition available. + Details
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Section B -Paragraph 7 -Subparagraph b -Chapter 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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