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Stock-based Compensation and Awards (Tables) | 12 Months Ended
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Dec. 31, 2011
Stock-based Compensation and Awards [Abstract] |
Summary of stock-based compensation expense |
|  | Years Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
Stock options |  | $ | 3,916 |  |  | $ | 5,273 |  |  | $ | 5,673 |
Restricted stock, restricted stock units and phantom units |  |  | 14,970 |  |  |  | 17,796 |  |  |  | 17,983 |
Employee stock purchase plan |  |  | 278 |  |  |  | 282 |  |  |  | 935 |
Total stock-based compensation expense |  | $ | 19,164 |  |  | $ | 23,351 |  |  | $ | 24,591 |
Weighted average fair value at date of grant for options granted |
|  | Years Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
Expected life in years |  |  | 4.5 |  |  |  | 4.5 |  |  |  | 4.5 |
Risk-free interest rate |  |  | 1.23 | % |  |  | 2.13 | % |  |  | 1.84 | %
Volatility |  |  | 45.17 | % |  |  | 42.94 | % |  |  | 40.51 | %
Dividend yield |  |  | 0.0 | % |  |  | 0.0 | % |  |  | 0.0 | %
Summary of stock option activity |
|  | Stock Options |  |  | Weighted Average Exercise Price |  |  | Weighted Average Remaining Life |  |  | Aggregate Intrinsic Value |
Options outstanding, December 31, 2010 |  |  | 3,124 |  |  | $ | 31.20 |  |  |  |  |  |  |  |  |
Granted |  |  | 924 |  |  |  | 15.33 |  |  |  |  |  |  |  |  |
Exercised |  |  | (33 | ) |  |  | 16.16 |  |  |  |  |  |  |  |  |
Cancelled |  |  | (744 | ) |  |  | 28.90 |  |  |  |  |  |  |  |  |
Options outstanding, December 31, 2011 |  |  | 3,271 |  |  |  | 27.39 |  |  |  | 4.1 |  |  | $ | — |
Options exercisable, December 31, 2011 |  |  | 2,029 |  |  |  | 34.20 |  |  |  | 2.9 |  |  |  | — |
Schedule of restricted stock and restricted stock unit activity |
|  | Shares |  |  | Weighted Average Grant-Date Fair Value Per Share |
Non-vested restricted stock and restricted stock units, December 31, 2010 |  |  | 1,421 |  |  | $ | 23.20 |
Granted |  |  | 1,212 |  |  |  | 19.22 |
Vested |  |  | (743 | ) |  |  | 25.36 |
Cancelled |  |  | (220 | ) |  |  | 22.11 |
Non-vested restricted stock and restricted stock units, December 31, 2011 |  |  | 1,670 |  |  |  | 19.49 |
Schedule of phantom unit activity |
|  | Phantom Units |  |  | Weighted Average Grant-Date Fair Value per Unit |
Phantom units outstanding, December 31, 2010 |  |  | 98,537 |  |  | $ | 19.23 |
Granted |  |  | 49,082 |  |  |  | 24.70 |
Vested |  |  | (67,026 | ) |  |  | 20.47 |
Cancelled |  |  | (5,326 | ) |  |  | 22.56 |
Phantom units outstanding, December 31, 2011 |  |  | 75,267 |  |  |  | 21.45 |

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- Definition Tabular disclosure of the number and weighted-average grant-date fair value for phantom units that were outstanding at the beginning and end of the year, granted, vested, forfeited or expired during the year. + References No definition available. + Details
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- Definition Tabular 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, granted, vested, forfeited or expired during the year. + References No definition available. + Details
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- Definition Tabular disclosure of the amount of total share-based compensation cost, including the amounts attributable to each share-based compensation plan and any related tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 718 -SubTopic 10 -Publisher FASB -Number -Article -Subparagraph (h)(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 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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