v2.4.0.6

Stock-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2011
Stock-Based Compensation [Abstract] |
Schedule Of Option Activity And Changes |
|  | Options |  |  | Weighted Average Exercise Price |  |  | Weighted Average Remaining Term (Years) |  |  | Aggregate Intrinsic Value |
Outstanding at December 31, 2010 |  |  | 1,314,524 |  |  | $ | 20.81 |  |  |  |  |  |  |  |  |
Granted |  |  | 99,380 |  |  |  | 45.83 |  |  |  |  |  |  |  |  |
Exercised |  |  | (274,872 | ) |  |  | 19.44 |  |  |  |  |  |  |  |  |
Cancelled |  |  | (5,885 | ) |  |  | 34.41 |  |  |  |  |  |  |  |  |
Outstanding at December 31, 2011 |  |  | 1,133,147 |  |  | $ | 23.26 |  |  |  | 6.5 |  |  | $ | 19,788 |
Exercisable at December 31, 2011 |  |  | 503,830 |  |  | $ | 18.74 |  |  |  | 5.8 |  |  | $ | 10,835 |
Schedule Of Range Of Exercise Prices For Outstanding Options |
Range of Prices |  | Options Outstanding |  |  | Weighted Average Remaining Contractual Life (Years) |
$14.24 – $19.29 |  |  | 505,268 |  |  |  | 6.2 |
$20.53 – $27.24 |  |  | 258,767 |  |  |  | 7.5 |
$30.07 – $45.83 |  |  | 369,112 |  |  |  | 6.2 |
Schedule Of Weighted Average Value And Assumptions For Fair Value Of Options |
|  | Stock Option Grants |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
Weighted average fair value |  | $ | 19.22 |  |  | $ | 8.31 |  |  | $ | 5.67 |
Risk-free interest rate |  |  | 2.8% |  |  |  | 2.9% |  |  |  | 2.8% |
Expected life in years |  |  | 6 |  |  |  | 6 |  |  |  | 6 – 7 |
Expected volatility |  |  | 41.9% |  |  |  | 41.8% |  |  |  | 42.5% |
Expected dividend yield |  |  | 0.5% |  |  |  | 1.1% |  |  |  | 1.5% |
Schedule Of Non-Vested Restricted Stock Award Activity And Changes |
|  | Number of Shares |  |  | Weighted Average Grant Date Fair Value |
Non-vested at December 31, 2010 |  |  | 654,241 |  |  | $ | 19.97 |
Granted |  |  | 78,828 |  |  |  | 45.03 |
Vested |  |  | (143,121 | ) |  |  | 19.64 |
Forfeited |  |  | (7,935 | ) |  |  | 20.48 |
Non-vested at December 31, 2011 |  |  | 582,013 |  |  | $ | 23.43 |

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- Definition Tabular disclosure of the changes in outstanding nonvested shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 718 -SubTopic 10 -Publisher FASB -Number -Article -Subparagraph (c)(2) -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 option exercise prices, by grouped ranges, including the upper and lower limits of the price range, the number of shares under option, weighted average exercise price and remaining contractual option terms. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64 -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph f -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. Reference 3: 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 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 718 -SubTopic 10 -Publisher FASB -Number -Article -Subparagraph (f)(2) -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 number of fully vested share options (or share units) and share options expected to vest at the date of the latest statement of financial position, weighted-average exercise price (or conversion ratio), aggregate intrinsic value (except for nonpublic entities), and weighted-average remaining contractual term for both options (or share units) currently outstanding and options (or share units) exercisable (or convertible). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 718 -SubTopic 10 -Publisher FASB -Number -Article -Subparagraph (e) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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