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Restricted Common Stock and Stock Appreciation Rights ("SARs") - Summary of Stock Option Activity (Detail) (USD $)
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9 Months Ended | |
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Sep. 30, 2013
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Sep. 30, 2012
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||
| Shares Under Options, Beginning balance | 750 | 3,500 |
| Shares Under Options, Exercised | (750) | (3,500) |
| Shares Under Options, Ending balance | ||
| Weighted Average Exercise Price, Beginning balance | $ 28.86 | $ 25.67 |
| Weighted Average Exercise Price, Exercised | $ 28.86 | $ 25.67 |
| Weighted Average Exercise Price, Ending balance | ||
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- Details
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- Definition
Number of options outstanding, including both vested and non-vested options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition
Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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