Earnings Per Share of Common Stock (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Diluted earnings per share of common stock:
Net income attributable to common stockholders	$ 376,868	$ 306,243
Weighted-average common stock outstanding applicable to basic earnings per share (in shares)	69,113	78,689
Effect of dilutive shares:
Common shares issuable under stock-based compensation plans (in shares)	4,004	3,319
Weighted-average shares of common stock applicable to diluted earnings per share (in shares)	73,117	82,008
Basic earnings per share of common stock (in dollars per share)	$ 5.45	$ 3.89
Diluted earnings per share of common stock (in dollars per share)	$ 5.15	$ 3.73
Total anti-dilutive shares and units (in shares)	217	384
Performance-based RSUs
Effect of dilutive shares:
Total anti-dilutive shares and units (in shares)	120	162
Time-based RSUs
Effect of dilutive shares:
Total anti-dilutive shares and units (in shares)		117
Stock Options
Effect of dilutive shares:
Total anti-dilutive shares and units (in shares)	97	105
Weighted-average exercise price of anti-dilutive stock options (in dollars per share)	$ 58.85	$ 35.03