|
Stock-Based Compensation (Tables)
|
9 Months Ended |
|
Sep. 30, 2014
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| Stock-Based Compensation |
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| Schedule of employee stock-based compensation expense |
|
|
|
Three Months Ended
|
|
Nine Months Ended
|
|
|
|
|
September 30,
|
|
September 30,
|
|
|
|
|
2014
|
|
2013
|
|
2014
|
|
2013
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Employee stock-based compensation expense
|
|
$
|
2,676
|
|
$
|
2,015
|
|
$
|
8,443
|
|
$
|
6,281
|
|
|
Tax effect on employee stock-based compensation expense
|
|
(1,070
|
)
|
(503
|
)
|
(3,377
|
)
|
(1,927
|
)
|
|
Net effect on income
|
|
$
|
1,606
|
|
$
|
1,512
|
|
$
|
5,066
|
|
$
|
4,354
|
|
|
| Schedule of weighted average assumptions used to value options granted |
|
|
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Three Months Ended
|
|
Nine Months Ended
|
|
|
|
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September 30,
|
|
September 30,
|
|
|
|
|
2014
|
|
2013
|
|
2014
|
|
2013
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Grant date fair value of options
|
|
$
|
16.80
|
|
$
|
—
|
|
$
|
16.81
|
|
$
|
6.11
|
|
|
Volatility
|
|
33.7
|
%
|
—
|
|
37.3
|
%
|
40.4
|
%
|
|
Risk-free interest rate
|
|
2.0
|
%
|
—
|
|
1.9
|
%
|
1.0
|
%
|
|
Dividend yield
|
|
—
|
|
—
|
|
—
|
|
—
|
|
|
Expected term (in years)
|
|
6.0
|
|
—
|
|
6.0
|
|
6.0
|
|
|
| Summary of option activity under the Company's plans |
|
|
|
Options
|
|
Weighted-
Average
Exercise Price
|
|
Weighted-
Average
Remaining
Contractual
Life (Years)
|
|
Aggregate
Intrinsic Value
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Outstanding as of December 31, 2013
|
|
4,637,471
|
|
$
|
9.04
|
|
|
|
|
|
|
Granted
|
|
155,753
|
|
41.84
|
|
|
|
|
|
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Exercised
|
|
(95,609
|
)
|
8.77
|
|
|
|
|
|
|
Forfeited
|
|
(4,150
|
)
|
9.00
|
|
|
|
|
|
|
Outstanding as of March 31, 2014
|
|
4,693,465
|
|
10.13
|
|
5.3
|
|
$
|
141,293
|
|
|
Granted
|
|
—
|
|
|
|
|
|
|
|
|
Exercised
|
|
(95,352
|
)
|
8.14
|
|
|
|
|
|
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Forfeited
|
|
(3,300
|
)
|
7.80
|
|
|
|
|
|
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Outstanding as of June 30, 2014
|
|
4,594,813
|
|
10.17
|
|
5.0
|
|
178,031
|
|
|
Granted
|
|
58,500
|
|
45.81
|
|
|
|
|
|
|
Exercised
|
|
(142,106
|
)
|
10.77
|
|
|
|
|
|
|
Forfeited
|
|
(533
|
)
|
9.87
|
|
|
|
|
|
|
Outstanding as of September 30, 2014
|
|
4,510,674
|
|
10.62
|
|
4.8
|
|
155,137
|
|
|
Options exercisable
|
|
4,022,167
|
|
8.69
|
|
4.4
|
|
146,046
|
|
|
| Summary of the activity for unvested restricted stock awards granted under the Company's plans |
|
|
|
|
|
Weighted-
|
|
|
|
|
|
|
Average Grant
|
|
|
|
|
Number of
|
|
Date Fair Value
|
|
|
|
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Shares
|
|
per Share
|
|
|
|
|
|
|
|
|
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Balance at December 31, 2013
|
|
901,551
|
|
$
|
16.50
|
|
|
Granted
|
|
240,626
|
|
41.83
|
|
|
Vested
|
|
(116,706
|
)
|
14.22
|
|
|
Forfeited
|
|
(10,324
|
)
|
26.94
|
|
|
Balance at March 31, 2014
|
|
1,015,147
|
|
22.69
|
|
|
Vested
|
|
(5,671
|
)
|
24.60
|
|
|
Forfeited
|
|
(4,312
|
)
|
29.79
|
|
|
Balance at June 30, 2014
|
|
1,005,164
|
|
22.65
|
|
|
Granted
|
|
8,527
|
|
46.62
|
|
|
Vested
|
|
(14,837
|
)
|
26.97
|
|
|
Forfeited
|
|
(5,336
|
)
|
28.72
|
|
|
Balance at September 30, 2014
|
|
993,518
|
|
22.76
|
|
|