|
Stock-Based Compensation (Tables)
|
12 Months Ended |
|
Dec. 31, 2013
|
| Stock-Based Compensation |
|
| Schedule of employee stock-based compensation expense |
|
|
|
Year ended December 31,
|
|
|
|
|
2013
|
|
2012
|
|
2011
|
|
|
|
|
|
|
|
|
|
|
|
Employee stock-based compensation expense
|
|
$
|
8,738
|
|
$
|
4,342
|
|
$
|
3,062
|
|
|
Tax effect on employee stock-based compensation expense
|
|
(3,196
|
)
|
(1,643
|
)
|
(1,159
|
)
|
|
Net effect on income
|
|
$
|
5,542
|
|
$
|
2,699
|
|
$
|
1,903
|
|
|
| Schedule of weighted average assumptions used to value options granted |
|
|
|
Year ended December 31,
|
|
|
|
|
2013
|
|
2012
|
|
2011
|
|
|
|
|
|
|
|
|
|
|
|
Grant date fair value of options
|
|
$
|
6.11
|
|
$
|
4.96
|
|
$
|
5.14
|
|
|
Volatility
|
|
40.4
|
%
|
39.7
|
%
|
39.4
|
%
|
|
Risk-free interest rate
|
|
1.0
|
%
|
1.2
|
%
|
2.37
|
%
|
|
Dividend yield
|
|
0.0
|
%
|
0.0
|
%
|
0.0
|
%
|
|
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
|
|
|
|
|
|
|
|
|
|
|
|
|
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Outstanding as of December 31, 2010
|
|
4,998,337
|
|
$
|
7.64
|
|
|
|
|
|
|
Granted
|
|
486,833
|
|
12.37
|
|
|
|
|
|
|
Exercised
|
|
(447,528
|
)
|
6.14
|
|
|
|
|
|
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Forfeited
|
|
(173,924
|
)
|
9.36
|
|
|
|
|
|
|
Outstanding as of December 31, 2011
|
|
4,863,718
|
|
8.19
|
|
6.8
|
|
$
|
18,704
|
|
|
Granted
|
|
738,915
|
|
12.53
|
|
|
|
|
|
|
Exercised
|
|
(298,947
|
)
|
6.92
|
|
|
|
|
|
|
Forfeited
|
|
(26,274
|
)
|
11.03
|
|
|
|
|
|
|
Outstanding as of December 31, 2012
|
|
5,277,412
|
|
8.86
|
|
6.3
|
|
26,885
|
|
|
Granted
|
|
190,413
|
|
15.34
|
|
|
|
|
|
|
Exercised
|
|
(721,050
|
)
|
8.86
|
|
|
|
|
|
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Forfeited
|
|
(109,304
|
)
|
12.33
|
|
|
|
|
|
|
Outstanding as of December 31, 2013
|
|
4,637,471
|
|
9.04
|
|
5.4
|
|
31,877
|
|
|
Options exercisable
|
|
3,417,153
|
|
8.08
|
|
4.6
|
|
110,111
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Schedule of other information |
|
|
|
Year ended December 31,
|
|
|
|
|
2013
|
|
2012
|
|
2011
|
|
|
|
|
|
|
|
|
|
|
|
Total intrinsic value of options exercised
|
|
$
|
13,745
|
|
$
|
1,611
|
|
$
|
3,082
|
|
|
Cash received from exercises of stock options
|
|
6,400
|
|
2,069
|
|
2,747
|
|
|
Cash received from issuance of restricted stock
|
|
1
|
|
2,759
|
|
—
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 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, 2010
|
|
—
|
|
$
|
—
|
|
|
Granted
|
|
77,224
|
|
12.38
|
|
|
Vested
|
|
—
|
|
—
|
|
|
Forfeited
|
|
(3,404
|
)
|
12.55
|
|
|
Balance at December 31, 2011
|
|
73,820
|
|
12.37
|
|
|
Granted
|
|
714,934
|
|
12.50
|
|
|
Vested
|
|
(24,568
|
)
|
—
|
|
|
Expired/cancelled
|
|
(1,064
|
)
|
12.45
|
|
|
Forfeited
|
|
(4,132
|
)
|
12.49
|
|
|
Balance at December 31, 2012
|
|
758,990
|
|
12.49
|
|
|
Granted
|
|
386,245
|
|
19.54
|
|
|
Vested
|
|
(74,298
|
)
|
—
|
|
|
Forfeited
|
|
(169,386
|
)
|
12.69
|
|
|
Balance at December 31, 2013
|
|
901,551
|
|
16.50
|
|
|
|
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