Stock-based Compensation Expense and Share Repurchase Programs - Stock Options Outstanding and Exercisable (Details) shares in Thousands	6 Months Ended
	Jun. 30, 2020 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price range, options outstanding (in shares) | shares	4,588
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	6 years 10 months 20 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 139.99
Exercise price range, options exercisable (in shares) | shares	2,623
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 121.00
$33.82–$40.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	33.82
Exercise price, high end of range (in dollars per share)	$ 40.00
Exercise price range, options outstanding (in shares) | shares	67
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	1 year 3 months 7 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 37.85
Exercise price range, options exercisable (in shares) | shares	67
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 37.85
$40.01–$60.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	40.01
Exercise price, high end of range (in dollars per share)	$ 60.00
Exercise price range, options outstanding (in shares) | shares	166
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	2 years 2 months 12 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 47.20
Exercise price range, options exercisable (in shares) | shares	166
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 47.20
$60.01–$80.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	60.01
Exercise price, high end of range (in dollars per share)	$ 80.00
Exercise price range, options outstanding (in shares) | shares	107
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	3 years 9 months 7 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 74.83
Exercise price range, options exercisable (in shares) | shares	105
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 74.83
$80.01–$100.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	80.01
Exercise price, high end of range (in dollars per share)	$ 100.00
Exercise price range, options outstanding (in shares) | shares	1,095
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	5 years 11 months 1 day
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 88.92
Exercise price range, options exercisable (in shares) | shares	889
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 89.33
$100.01–$120.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	100.01
Exercise price, high end of range (in dollars per share)	$ 120.00
Exercise price range, options outstanding (in shares) | shares	132
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	4 years 7 months 20 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 109.27
Exercise price range, options exercisable (in shares) | shares	130
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 109.20
$120.01–$140.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	120.01
Exercise price, high end of range (in dollars per share)	$ 140.00
Exercise price range, options outstanding (in shares) | shares	288
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	5 years 2 months 23 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 129.41
Exercise price range, options exercisable (in shares) | shares	286
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 129.43
$140.01–$160.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	140.01
Exercise price, high end of range (in dollars per share)	$ 160.00
Exercise price range, options outstanding (in shares) | shares	784
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	7 years 7 months 9 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 155.49
Exercise price range, options exercisable (in shares) | shares	340
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 155.39
$160.01–$180.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	160.01
Exercise price, high end of range (in dollars per share)	$ 180.00
Exercise price range, options outstanding (in shares) | shares	619
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	8 years 7 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 168.32
Exercise price range, options exercisable (in shares) | shares	252
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 165.43
$180.01–$200.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	180.01
Exercise price, high end of range (in dollars per share)	$ 200.00
Exercise price range, options outstanding (in shares) | shares	1,307
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	8 years 4 months 24 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 185.32
Exercise price range, options exercisable (in shares) | shares	365
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 184.82
$200.01–$286.27
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Exercise price, low end of range (in dollars per share)	200.01
Exercise price, high end of range (in dollars per share)	$ 286.27
Exercise price range, options outstanding (in shares) | shares	23
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	9 years 11 months 1 day
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 286.27
Exercise price range, options exercisable (in shares) | shares	23
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 286.27