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Share-Based Payments (Tables) | 12 Months Ended
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Dec. 31, 2011
Share-Based Payments [Abstract] |
Summary of Stock Option Transactions under our Share-Based Payment Plans |
|  |  |  |  | Weighted |  |
|  |  | Weighted |  | Average |  |
|  |  | Average |  | Remaining |  | Aggregate
| Number |  | Exercise |  | Contractual |  | Intrinsic Value
| of Shares |  | Price |  | Life in Years |  | ($ in thousands)
Outstanding at December 31, 2010 | 1,402,256 | $ | 18.08 |  |  |  |
Granted 2011 | - |  | - |  |  |  |
Exercised 2011 | 135,196 |  | 11.26 |  |  |  |
Forfeited or expired 2011 | 27,373 |  | 20.58 |  |  |  |
Outstanding at December 31, 2011 | 1,239,687 | $ | 18.78 |  | 5.20 | $ | 2,381
Exercisable at December 31, 2011 | 1,130,901 | $ | 19.08 |  | 4.95 | $ | 2,135
Summary of Restricted Stock and Restricted Stock Units Transactions under our Share-Based Payment Plans |
|  |  | Weighted
|  |  | Average
| Number |  | Grant Date
| of Shares |  | Fair Value
Unvested restricted stock and RSU awards at December 31, 2010 | 1,241,900 | $ | 16.85
Granted 2011 | 429,420 |  | 17.17
Vested 2011 | 361,305 |  | 22.45
Forfeited 2011 | 26,495 |  | 14.74
Unvested RSU awards at December 31, 2011 | 1,283,520 | $ | 15.45
Weighted Average Assumptions for Employee Stock Purchase Plan and Other Options |
| ESPP |  | All Other Option Plans |
| 2011 |  | 2010 |  | 2009 |  | 2011 |  | 2010 |  | 2009 |  |
Risk-free interest rate | 0.13 | % | 0.20 |  | 0.31 |  | - |  | 2.30 |  | 1.85 |  |
Expected term | 6 months |  | 6 months |  | 6 months |  | - |  | 5 years |  | 5 years |  |
Dividend yield | 3.0 | % | 3.3 |  | 3.4 |  | - |  | 3.3 |  | 3.9 |  |
Expected volatility | 19 | % | 28 |  | 64 |  | - |  | 34 |  | 32 |  |
Weighted-Average Fair Value of Options and Stock Per Share |
|  | 2011 |  | 2010 |  | 2009
Stock options | $ | - |  | 3.83 |  | 2.68
Restricted stock and RSUs |  | 17.17 |  | 14.69 |  | 14.22
Directors' stock compensation plan |  | - |  | 16.09 |  | 15.11
ESPP: |  |  |  |  |  |
Six month option |  | 0.76 |  | 1.03 |  | 2.51
15% of grant date market value |  | 2.62 |  | 2.35 |  | 2.49
Total ESPP |  | 3.38 |  | 3.38 |  | 5.00
Agent Plan: |  |  |  |  |  |
Discount of grant date market value |  | 1.62 |  | 1.59 |  | 1.39

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans and all other option plans, including, but not limited to: (a) expected term, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References No definition available. + Details
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- Definition Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. + References No definition available. + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 718 -SubTopic 10 -Publisher FASB -Number -Article -Subparagraph (c)(1) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the weighted-average grant-date fair value of equity options or other equity instruments granted during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 718 -SubTopic 10 -Publisher FASB -Number -Article -Subparagraph (d)(1) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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