v2.4.1.9

Share-based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2014
Summary of Stock Option Activity | The following table summarizes the Company’s stock option activity (in thousands, except per share data and years) for the periods indicated:
|  | Stock Options Outstanding |
|  | Shares |  |  | Weighted Average Exercise Price Per Share |  |  | Aggregate Intrinsic Value |  |  | Weighted Average Remaining Contractual Term (Years) |
Balance as of January 1, 2012 |  |  | 517 |  |  | $ | 20.31 |  |  |  |  |  |  |  |  |
Granted |  |  | 0 |  |  |  | 0 |  |  |  |  |  |  |  |  |
Exercised |  |  | (501 | ) |  |  | 20.30 |  |  | $ | 51,564 |  |  |  |  |
Forfeited/Expired |  |  | 0 |  |  |  | 0 |  |  |  |  |  |  |  |  |
Balance as of December 31, 2012 |  |  | 16 |  |  | $ | 20.81 |  |  |  |  |  |  |  |  |
Granted |  |  | 600 |  |  |  | 92.84 |  |  |  |  |  |  |  |  |
Exercised |  |  | (16 | ) |  |  | 20.81 |  |  | $ | 1,262 |  |  |  |  |
Forfeited/Expired |  |  | 0 |  |  |  | 0 |  |  |  |  |  |  |  |  |
Balance as of December 31, 2013 |  |  | 600 |  |  | $ | 92.84 |  |  |  |  |  |  |  |  |
Granted |  |  | 745 |  |  |  | 125.46 |  |  |  |  |  |  |  |  |
Exercised |  |  | (9 | ) |  |  | 92.84 |  |  | $ | 653 |  |  |  |  |
Forfeited/Expired |  |  | (135 | ) |  |  | 104.48 |  |  |  |  |  |  |  |  |
Balance as of December 31, 2014 |  |  | 1,201 |  |  | $ | 111.77 |  |  |  |  |  |  |  |  |
Exercisable as of December 31, 2014 |  |  | 141 |  |  | $ | 92.84 |  |  | $ | 9,794 |  |  |  | 7.7 |
Expected to vest as of December 31, 2014 |  |  | 1,060 |  |  | $ | 114.29 |  |  |  | 51,001 |  |  |  | 9.1 |
Total |  |  | 1,201 |  |  | $ | 111.77 |  |  | $ | 60,795 |  |  |  | 9.0 |
Range Of Exercise Prices | Stock options outstanding as of December 31, 2014 are comprised of the following range of exercise prices per share (in thousands, except per share data and years):
|  | Stock Options Outstanding at December 31, 2014 |
Range of Exercise Prices per Share |  | Shares |  |  | Weighted Average Exercise Price Per Share |  |  | Weighted Average Remaining Contractual Term (Years) |
$92.84 - $120.00 |  |  | 596 |  |  | $ | 96.34 |  |  |  | 8.5 |
$120.01 - $150.00 |  |  | 520 |  |  | $ | 121.43 |  |  |  | 9.3 |
$150.01 - $160.88 |  |  | 85 |  |  | $ | 160.88 |  |  |  | 9.8 |
Total |  |  | 1,201 |  |  | $ | 111.77 |  |  |  | 9.0 |
Assumptions Used in Black-Scholes Option-Pricing Model | The weighted average grant date fair value of stock option awards using the Black-Scholes option pricing model was $55.84 and $42.03 for each share subject to a stock option granted during the years ended December 31, 2014 and December 31, 2013, respectively, based on the following assumptions:
|  | Years Ended December 31, |
|  | 2014 |  |  | 2013 |
Expected term of options in years |  |  | 6.3 |  |  |  | 6.3 |
Expected volatility |  |  | 41.5 - 42.5 | % |  |  | 42.8 | %
Risk-free interest rate |  |  | 2.1 - 2.3 | % |  |  | 2.5 | %
Expected dividend yield |  |  | 0.0 | % |  |  | 0.0 | %

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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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