v2.4.0.8

Stock-based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2013
Stock-based Compensation [Abstract] |
Schedule of weighted average assumptions |
|  | 2013 |  |  | 2012 |  |  | 2011 |
Expected term (in years) |  |  | 3.1 |  |  |  | 3.0 |  |  |  | 3.0 |
Expected volatility |  |  | 39 | % |  |  | 46 | % |  |  | 54 | %
Risk-free interest rate |  |  | 0.5 | % |  |  | 0.3 | % |  |  | 1.4 | %
Expected dividend yield |  |  | 0 | % |  |  | 0 | % |  |  | 0 | %
Schedule of summary of option activity |
|  | Shares |  |  | Weighted Average Exercise Price |  |  | Weighted-Average Remaining Contractual Life (Years) |  |  | Aggregate Intrinsic Value (amounts in thousands) |
Outstanding at January 1, 2013 |  |  | 438,693 |  |  | $ | 10.72 |  |  |  |  |  |  |
Granted |  |  | 55,000 |  |  |  | 41.93 |  |  |  |  |  |  |
Exercised |  |  | (229,506 | ) |  |  | 7.62 |  |  |  |  |  |  |
Outstanding at December 31, 2013 |  |  | 264,187 |  |  |  | 19.90 |  |  | 2.1 |  |  | $ | 10,133 |
Exercisable at December 31, 2013 |  |  | 254,187 |  |  |  | 18.94 |  |  | 2.0 |  |  |  | 9,994 |
Schedule of summary of restricted stock activity |
|  | Shares |  |  | Weighted Average Grant-Date Fair Value |
Non-vested at January 1, 2013 |  |  | 205,650 |  |  | $ | 27.94 |
Granted |  |  | 126,000 |  |  |  | 46.80 |
Vested |  |  | (73,500 | ) |  |  | 26.70 |
Forfeited |  |  | (21,200 | ) |  |  | 37.25 |
Non-vested at December 31, 2013 |  |  | 236,950 |  |  |  | 37.24 |

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