Stock-Based Compensation (Details 2) (Stock Options, USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
$1.90 - $2.88
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 1.90
Exercise price, high end of range (in dollars per share)	$ 2.88
Options Outstanding
Number of Shares	5
Weighted Average Remaining Contractual Life	3 months 22 days
Weighted Average Exercise Price (in dollars per share)	$ 1.90
Options Exercisable
Number of Shares	5
Weighted Average Exercise Price (in dollars per share)	$ 1.90
$6.38 - $7.94
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 6.38
Exercise price, high end of range (in dollars per share)	$ 7.94
Options Outstanding
Number of Shares	129
Weighted Average Remaining Contractual Life	2 years 2 months 1 day
Weighted Average Exercise Price (in dollars per share)	$ 6.53
Options Exercisable
Number of Shares	129
Weighted Average Exercise Price (in dollars per share)	$ 6.53
$10.73 - $12.90
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 10.73
Exercise price, high end of range (in dollars per share)	$ 12.90
Options Outstanding
Number of Shares	678
Weighted Average Remaining Contractual Life	6 years 8 months 19 days
Weighted Average Exercise Price (in dollars per share)	$ 11.66
Options Exercisable
Number of Shares	440
Weighted Average Exercise Price (in dollars per share)	$ 11.78
$13.15 - $15.03
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 13.15
Exercise price, high end of range (in dollars per share)	$ 15.03
Options Outstanding
Number of Shares	331
Weighted Average Remaining Contractual Life	6 years 5 months 5 days
Weighted Average Exercise Price (in dollars per share)	$ 13.54
Options Exercisable
Number of Shares	236
Weighted Average Exercise Price (in dollars per share)	$ 13.41
$1.90 - $15.03
Stock-Based Compensation
Exercise price, low end of range (in dollars per share)	$ 1.90
Exercise price, high end of range (in dollars per share)	$ 15.03
Options Outstanding
Number of Shares	1,143
Weighted Average Remaining Contractual Life	6 years 1 month 6 days
Weighted Average Exercise Price (in dollars per share)	$ 11.59
Options Exercisable
Number of Shares	810
Weighted Average Exercise Price (in dollars per share)	$ 11.36