Stock Option and Compensation Plans (Details 2) (Stock option, USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Options Outstanding
Total Options Outstanding (in shares)	2,708
Aggregate Intrinsic Value	$ 62,185
Options Exercisable
Number Exercisable (in shares)	984
Aggregate Intrinsic Value	$ 29,107
$0.12-$10.03
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	$ 0.12
Exercise prices, high end of range (in dollars per share)	$ 10.03
Options Outstanding
Total Options Outstanding (in shares)	1,800
Weighted Average Remaining Life	7 years 9 months 18 days
Weighted Average Exercise Price (in dollars per share)	$ 4.89
Options Exercisable
Number Exercisable (in shares)	969
Weighted Average Exercise Price (in dollars per share)	$ 2.50
$10.04-$20.00
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	$ 10.04
Exercise prices, high end of range (in dollars per share)	$ 20.00
Options Outstanding
Total Options Outstanding (in shares)	604
Weighted Average Remaining Life	9 years 6 months
Weighted Average Exercise Price (in dollars per share)	$ 13.37
Options Exercisable
Number Exercisable (in shares)	10
Weighted Average Exercise Price (in dollars per share)	$ 13.22
$20.01-$33.27
Range of Exercise Prices
Exercise prices, low end of range (in dollars per share)	$ 20.01
Exercise prices, high end of range (in dollars per share)	$ 33.27
Options Outstanding
Total Options Outstanding (in shares)	304
Weighted Average Remaining Life	9 years 9 months 18 days
Weighted Average Exercise Price (in dollars per share)	$ 28.34
Options Exercisable
Number Exercisable (in shares)	5
Weighted Average Exercise Price (in dollars per share)	$ 32.58