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Stockholders' Equity - Additional Information (Detail) (USD $) |  |  |  |  |  |  |  | 5 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2014 | Nov. 30, 2013 | Feb. 28, 2013 | Aug. 31, 2011 | Mar. 31, 2011 | Aug. 31, 2010 | May 31, 2010 | Nov. 30, 2013 Fifth Share Repurchase Program | Jun. 30, 2014 Sixth Share Repurchase Program | Nov. 30, 2013 Sixth Share Repurchase Program
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |
Share repurchase program, authorized amount | $ 1,000,000,000 | $ 300,000,000 | $ 200,000,000 | $ 200,000,000 | $ 100,000,000 | $ 100,000,000 | $ 100,000,000 | $ 200,000,000 |  | $ 300,000,000
Shares repurchased |  |  |  |  |  |  |  | $ 153,000,000 | $ 134,000,000 |

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- Definition Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate 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 SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 + Details
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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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