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Commitments And Contingencies (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2012 LawSuits | Mar. 07, 2012 Event
Commitment And Contingencies [Line Items] |  |
Number of causes of actions purported |  | 7
Other material lawsuits pending | 0 |
5.700% Senior Notes Due 2034 [Member] |  |
Commitment And Contingencies [Line Items] |  |
Long-term debt, interest rate | 5.70% |
Long-term debt, maturity, year | 2034 |

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- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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