Stock-based Compensation Expense and Share Repurchase Programs - Stock Options Outstanding and Exercisable (Details) shares in Thousands	9 Months Ended
	Sep. 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	4,378
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	6 years 7 months 17 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 140.26
Exercise price range, options exercisable (in shares) | shares	2,747
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 123.22
$36.28–$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)	36.28
Exercise price, high end of range (in dollars per share)	$ 40.00
Exercise price range, options outstanding (in shares) | shares	62
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	1 year 1 month 2 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 38.06
Exercise price range, options exercisable (in shares) | shares	62
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 38.06
$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	157
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	1 year 11 months 23 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 47.13
Exercise price range, options exercisable (in shares) | shares	157
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 47.13
$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	105
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	3 years 5 months 26 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 74.82
Exercise price range, options exercisable (in shares) | shares	104
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 74.82
$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	1,029
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	5 years 7 months 28 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 88.91
Exercise price range, options exercisable (in shares) | shares	919
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 89.20
$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	129
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	4 years 4 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	128
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 109.21
$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	282
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	4 years 11 months 23 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 129.42
Exercise price range, options exercisable (in shares) | shares	281
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	740
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	7 years 4 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	369
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 155.41
$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	599
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	7 years 9 months 3 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 168.34
Exercise price range, options exercisable (in shares) | shares	282
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 165.74
$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	1,252
Exercise price range, options outstanding, weighted-average remaining contractual life (in years)	8 years 1 month 20 days
Exercise price range, options outstanding, weighted-average exercise price (in dollars per share)	$ 185.31
Exercise price range, options exercisable (in shares) | shares	422
Exercise price range, options exercisable, weighted-average exercise price (in dollars per share)	$ 184.85
$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 8 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