Stock-based Compensation Expense (Details 2) shares in Thousands	9 Months Ended
	Sep. 30, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price range, options outstanding (in shares) | shares	12,025
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	7 years 3 months 22 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 74.90
Exercise price range, options exercisable (in shares) | shares	5,438
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 53.98
$18.93–$20.00
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price, low end of range (usd per share)	18.93
Exercise price, high end of range (usd per share)	$ 20.00
Exercise price range, options outstanding (in shares) | shares	138
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	2 years 4 months 6 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 18.93
Exercise price range, options exercisable (in shares) | shares	138
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 18.93
$20.01–$40.00
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price, low end of range (usd per share)	20.01
Exercise price, high end of range (usd per share)	$ 40
Exercise price range, options outstanding (in shares) | shares	2,499
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	3 years 9 months 22 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 34.56
Exercise price range, options exercisable (in shares) | shares	2,284
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 34.36
$40.01–$60.00
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price, low end of range (usd per share)	40.01
Exercise price, high end of range (usd per share)	$ 60
Exercise price range, options outstanding (in shares) | shares	2,593
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	6 years 9 months 18 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 48.27
Exercise price range, options exercisable (in shares) | shares	1,458
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 49.52
$60.01–$80.00
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price, low end of range (usd per share)	60.01
Exercise price, high end of range (usd per share)	$ 80
Exercise price range, options outstanding (in shares) | shares	1,567
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	8 years 3 months 22 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 75.94
Exercise price range, options exercisable (in shares) | shares	551
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 74.95
$80.01–$100.00
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price, low end of range (usd per share)	80.01
Exercise price, high end of range (usd per share)	$ 100
Exercise price range, options outstanding (in shares) | shares	1,932
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	8 years 3 months 11 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 90.27
Exercise price range, options exercisable (in shares) | shares	638
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 87.16
$100.01–$120.00
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price, low end of range (usd per share)	100.01
Exercise price, high end of range (usd per share)	$ 120
Exercise price range, options outstanding (in shares) | shares	1,791
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	9 years 3 months 26 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 109.24
Exercise price range, options exercisable (in shares) | shares	201
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 109.22
$120.01–$134.69
Share-based Compensation Arrangement by Share-based Payment Award
Exercise price, low end of range (usd per share)	120.01
Exercise price, high end of range (usd per share)	$ 134.69
Exercise price range, options outstanding (in shares) | shares	1,505
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	9 years 9 months 11 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 131.21
Exercise price range, options exercisable (in shares) | shares	168
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 127.52