Stock-Based Compensation Unrestricted Stock Awards Summary (Details) (Unrestricted Stock Award [Member], USD $) | 3 Months Ended | 9 Months Ended | ||
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Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | |
Unrestricted Stock Award [Member] | ||||
| [Line Items] | ||||
| Shares of unrestricted stock issued | 2,864 | 2,896 | 6,317 | 5,662 |
| Weighted average grant date fair value | $ 48.84 | $ 60.39 | $ 52.19 | $ 64.35 |
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan 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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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- Definition Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.
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