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Basis of Presentation - Common Share Amounts Used to Compute Basic and Diluted Earnings per Share (Detail)
In Millions, unless otherwise specified |
12 Months Ended | ||
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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| Earnings Per Share [Abstract] | |||
| Weighted average shares used in basic computations | 86.3us-gaap_WeightedAverageNumberOfSharesOutstandingBasic | 102.6us-gaap_WeightedAverageNumberOfSharesOutstandingBasic | 112.4us-gaap_WeightedAverageNumberOfSharesOutstandingBasic |
| Dilutive effect of exercise of equity grants outstanding | 4.5us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements | 4.8us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements | 5.5us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements |
| Weighted average shares used in diluted computations | 90.8us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding | 107.4us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding | 117.9us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding |
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- Details
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- Definition
Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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