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Share-Based Payments (Tables) | 12 Months Ended
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Dec. 31, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
Summary of Stock Option Transactions under our Share- Based Payment Plants |
|  | Number of Shares |  | Weighted Average Exercise Price |  | Weighted Average Remaining Contractual Life in Years |  | Aggregate Intrinsic Value ($ in thousands)
Outstanding at December 31, 2011 |  | 1,239,687 |  |  | $ | 18.78 |  |  |  |  |  |
Granted 2012 |  | — |  |  | — |  |  |  |  |  |
Exercised 2012 |  | 118,012 |  |  | 12.16 |  |  |  |  |  |
Forfeited or expired 2012 |  | 24,921 |  |  | 24.06 |  |  |  |  |  |
Outstanding at December 31, 2012 |  | 1,096,754 |  |  | $ | 19.36 |  |  | 4.59 |  | $ | 2,598 |
Exercisable at December 31, 2012 |  | 1,062,409 |  |  | $ | 19.48 |  |  | 4.50 |  | $ | 2,469 |
Summary of Restricted Stock Units Transactions under our Share-Based Payment Plans |
|  | Number of Shares |  | Weighted Average Grant Date Fair Value
Unvested RSU awards at December 31, 2011 |  | 1,283,520 |  |  | $ | 15.45 |
Granted 2012 |  | 399,326 |  |  | 17.62 |
Vested 2012 |  | 472,363 |  |  | 14.59 |
Forfeited 2012 |  | 73,113 |  |  | 15.97 |
Unvested RSU awards at December 31, 2012 |  | 1,137,370 |  |  | $ | 16.54 |
Weighted Average Assumptions for Employee Stock Purchase Plan and Other Options |
|  | ESPP |  | All Other Option Plans
|  | 2012 |  | 2011 |  | 2010 |  | 2012 |  | 2011 |  | 2010
Risk-free interest rate |  | 0.12 | % |  | 0.13 |  | 0.20 |  | — |  | — |  | 2.30
Expected term |  | 6 months |  |  | 6 months |  | 6 months |  | 0 |  | 0 |  | 5 years
Dividend yield |  | 2.9 | % |  | 3.0 |  | 3.3 |  | — |  | — |  | 3.3
Expected volatility |  | 24 | % |  | 19 |  | 28 |  | — |  | — |  | 34
Weighted-Average Fair Value of Options and Stock Per Share |
|  | 2012 |  | 2011 |  | 2010
Stock options |  | $ | — |  |  | — |  |  | 3.83 |
RSUs |  | 17.62 |  |  | 17.17 |  |  | 14.69 |
Directors’ stock compensation plan |  | — |  |  | — |  |  | 16.09 |
ESPP: |  |  |  |  |  |  |  |
Six month option |  | 1.05 |  |  | 0.76 |  |  | 1.03 |
15% of grant date market value |  | 2.70 |  |  | 2.62 |  |  | 2.35 |
Total ESPP |  | 3.75 |  |  | 3.38 |  |  | 3.38 |
Agent Plan: |  |  |  |  |  |  |  |  |
Discount of grant date market value |  | 1.76 |  |  | 1.62 |  |  | 1.59 |

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -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 -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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