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Roll-forward of Common Stock, Additional Paid-in Capital, and Retained Earnings Accounts (Parenthetical) (Detail) (Retained Earnings, USD $)
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12 Months Ended | ||
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Dec. 31, 2011
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Dec. 31, 2010
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Dec. 31, 2009
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Retained Earnings
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| Stockholders Equity Note [Line Items] | |||
| Dividends, per share | $ 2.08 | $ 1.88 | $ 1.80 |
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- Details
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- Definition
Aggregate dividends paid during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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