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Restricted Common Stock and Stock Appreciation Rights ("SARs") - Summary of Restricted Common Stock Activity (Detail) (Restricted common stock [Member], 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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Restricted common stock [Member]
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Stock beginning balance, Shares | 27,999 | 24,499 |
| Issued/Granted, Shares | 750 | 3,500 |
| Stock ending balance, Shares | 28,749 | 27,999 |
| Stock vested ending balance, Shares | 26,605 | 22,682 |
| Restricted stock unvested ending balance, Shares | 2,144 | 5,317 |
| Restricted stock beginning balance, Weighted average grant date fair value | $ 23.36 | $ 23.36 |
| Issued/Granted, Weighted average grant date fair value | $ 28.86 | $ 25.67 |
| Restricted stock ending balance, Weighted average grant date fair value | $ 23.76 | $ 23.67 |
| Restricted stock vested ending balance, Weighted average grant date fair value | ||
| Restricted stock unvested ending balance, Weighted average grant date fair value | ||
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Unvested Outstanding No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Unvested Weighted Average Grant Date Fair Value No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Weighted Average Grant Date Fair Value No definition available.
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- Definition
The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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