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Shareholders' Equity, Stock Options and Net Income per Share - Employee Activity Non-vested Shares (Details) (USD $)
In Thousands, except Share data, unless otherwise specified |
12 Months Ended | 3 Months Ended | 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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Mar. 31, 2011
Employee Non-vested Shares [Member]
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Dec. 31, 2011
Employee Non-vested Shares [Member]
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Dec. 31, 2009
Employee Non-vested Shares [Member]
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Dec. 31, 2006
Employee Non-vested Shares [Member]
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
| Nonvested shares granted to key employees | 107,505 | 129,350 | |||||
| Weighted average grant date fair value of non-vested shares | $ 28.61 | $ 36.09 | |||||
| Share-based awards, vesting period | 3 years | ||||||
| Share-based compensation | $ 5,971 | $ 6,284 | $ 6,754 | $ 895 | $ 258 | ||
| Tax benefit related to share-based compensation expense | 347 | 109 | |||||
| Unrecognized compensation cost | 2,094 | ||||||
| Number of non-vested shares that vested during the year | 37,632 | ||||||
| Grant date fair value of shares that vested during the year | $ 1,358 | ||||||
| X | ||||||||||
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- Definition
As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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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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| X | ||||||||||
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- Definition
The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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