Stock-Based Compensation (Tables)
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9 Months Ended |
Sep. 30, 2015 |
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| Stock-Based Compensation |
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| Schedule of employee stock-based compensation expense |
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Three Months Ended
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Nine Months Ended
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September 30,
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September 30,
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2015
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2014
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2015
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2014
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Employee stock-based compensation expense
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$
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3,408
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$
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2,676
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$
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10,157
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$
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8,443
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Tax effect on employee stock-based compensation expense
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(1,363)
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(1,070)
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(4,063)
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(3,377)
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Net effect on income
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$
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2,045
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$
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1,606
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$
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6,094
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$
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5,066
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| Schedule of weighted average assumptions used to value options granted |
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Three Months Ended
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Nine Months Ended
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September 30,
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September 30,
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2015
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2014
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2015
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2014
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Grant date fair value of options
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—
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$
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16.80
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$
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20.90
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$
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16.81
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Volatility
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—
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33.7
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%
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37.2
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%
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37.3
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%
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Risk-free interest rate
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—
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2.0
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%
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1.7
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%
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1.9
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%
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Dividend yield
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—
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—
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%
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—
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%
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—
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%
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Expected term (in years)
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—
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6.0
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6.0
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6.0
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| Summary of option activity under the Company's plans |
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Weighted-Average
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Weighted-
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Remaining
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Average
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Contractual Life
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Aggregate
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Options
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Exercise Price
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(Years)
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Intrinsic Value
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Outstanding as of December 31, 2014
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4,265,337
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$
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10.73
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4.7
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$
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163,830
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Granted
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148,677
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54.02
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Exercised
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(415,512)
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8.93
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Forfeited
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(9,941)
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24.94
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Outstanding as of March 31, 2015
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3,988,561
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12.50
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4.8
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173,837
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Granted
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123,410
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52.67
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Exercised
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(271,004)
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8.12
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Forfeited
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(28,403)
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46.07
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Outstanding as of June 30, 2015
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3,812,564
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13.86
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4.8
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105,196
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Granted
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—
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—
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Exercised
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(249,970)
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6.15
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Forfeited
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(2,403)
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47.33
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Outstanding as of September 30, 2015
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3,560,191
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14.38
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4.8
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64,068
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Options exercisable
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3,234,095
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11.53
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4.4
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63,173
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| Summary of the activity for unvested restricted stock awards granted under the Company's plans |
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Weighted-
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Average Grant
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Number of
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Date Fair Value
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Shares
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per Share
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Outstanding as of December 31, 2014
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1,098,674
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$
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33.72
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Granted
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207,531
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53.89
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Vested
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(358,166)
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20.44
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Expired/cancelled
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—
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—
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Forfeited
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(6,628)
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33.53
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Outstanding as of March 31, 2015
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941,411
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38.61
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Granted
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—
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—
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Vested
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—
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—
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Forfeited
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(5,869)
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45.98
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Outstanding as of June 30, 2015
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935,542
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43.18
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Granted
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2,000
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45.21
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Vested
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(17,126)
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30.29
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Forfeited
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(2,414)
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44.84
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Outstanding as of September 30, 2015
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918,002
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43.42
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