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Stock-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2012
Share-based Compensation [Abstract] |
A summary of the status of the stock option plans and changes during the year | A summary of the status of the stock option plans at December 31, 2012, and changes during the year then ended was as follows:
| Number of Shares |  | Weighted Average Exercise Price |
Balance at beginning of year | 6,750 |  | $ | 13.03 |
Exercised | (6,750 | ) | 13.03 |
Balance at end of year | — |  | — |
Target grants performance share | Target grants of performance shares outstanding at December 31, 2012, were as follows:
Grant Date | Performance Period | Target Grant of Shares |
March 2010 | 2010-2012 | 213,432 |
February 2011 | 2011-2013 | 261,029 |
February 2012 | 2012-2014 | 311,675 |
Schedule of share-based payment award, stock options, valuation assumptions | Assumptions used for grants of performance shares issued in 2012, 2011 and 2010 were:
|  |  | 2012 |  |  |  | 2011 |  |  |  | 2010 |
Grant-date fair value |  |  |  | $17.18 |  |  |  |  | $19.99 |  |  |  |  | $17.40 |
Blended volatility range | 24.29 | % | - | 25.81 | % | 23.20 | % | - | 32.18 | % | 25.69 | % | - | 35.36 | %
Risk-free interest rate range | .10 | % | - | .35 | % | .09 | % | - | 1.34 | % | .13 | % | - | 1.45 | %
Discounted dividends per share |  |  |  | $1.19 |  |  |  |  | $1.23 |  |  |  |  | $1.04 |
A summary of the status of the performance share awards | A summary of the status of the performance share awards for the year ended December 31, 2012, was as follows:
| Number of Shares |  | Weighted Average Grant-Date Fair Value |
Nonvested at beginning of period | 762,154 |  | $ | 19.35 |
Granted | 320,692 |  | 17.18 |
Vested | — |  | — |
Forfeited | (296,710 | ) | 20.13 |
Nonvested at end of period | 786,136 |  | $ | 18.17 |

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- Definition Tabular disclosure of components of a stock option or other award plan under which equity-based compensation is awarded to employees, typically comprised of the amount of unearned compensation (deferred compensation cost), compensation expense, and changes in the quantity and fair value of the shares (or other type of equity) granted, exercised, forfeited, and issued and outstanding pertaining to that plan. Disclosure may also include nature and general terms of such arrangements that existed during the period and potential effects of those arrangements on shareholders, effect of compensation cost arising from equity-based payment arrangements on the income statement, method of estimating the fair value of the goods or services received, or the fair value of the equity instruments granted, during the period, cash flow effects resulting from equity-based payment arrangements and, for registrants that accelerate vesting of out of the money share options, reasons for the decision to accelerate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64, 65, A240 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Tabular disclosure of the changes in outstanding nonvested performance-based units. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the changes in outstanding nonvested shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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