Share-Based Compensation and Benefit Plans (Summary of Stock Options) (Details) - Stock option [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-Based Compensation and Benefit Plans
Exercisable at the end of the year, average remaining contractual term	4 years 7 months 6 days	4 years 4 months 24 days	3 years 9 months 18 days
Employee stock option [Member]
Share-Based Compensation and Benefit Plans
Outstanding beginning balance, shares	1,860
Outstanding at the beginning of the year, weighted-average exercise price	$ 178.57
Granted, shares	214
Granted, weighted-average exercise price	$ 370.63
Exercised, shares	(406)
Exercised, weighted-average exercise price	$ 113.66
Forfeited or expired, shares	(33)
Forfeited or expired, weighted-average exercise price	$ 263.15
Outstanding ending balance, shares	1,635	1,860
Outstanding at the end of the year, weighted-average exercise price	$ 218.10	$ 178.57
Outstanding at the end of the year, average remaining contractual term	5 years 10 months 24 days
Outstanding at the end of the year, aggregate intrinsic value	$ 360,003
Vested or expected to vest at the end of the year, shares	1,598
Vested or expected to vest at the end of the year, weighted-average exercise price	$ 215.97
Vested or expected to vest at the end of the year, average remaining contractual term	5 years 10 months 24 days
Vested or expected to vest at the end of the year, aggregate intrinsic value	$ 355,172
Exercisable at the end of the year, shares	1,033
Exercisable at the end of the year, weighted-average exercise price	$ 170.77
Exercisable at the end of the year, average remaining contractual term	4 years 7 months 6 days
Exercisable at the end of the year, aggregate intrinsic value	$ 276,414