Stock-Based Compensation - Schedule of Stock Option Plans Activity (Detail) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding at beginning of year, Shares	3,892	3,828	4,106
Granted, Shares	529	489	265
Exercised, Shares	(266)	(425)	(543)
Canceled, Shares	(239)
Outstanding at end of year, Shares	3,916	3,892	3,828
Stock options exercisable at end of year, Shares	3,168	3,276	2,112
Outstanding at beginning of year, Weighted - Average Exercise Price	$ 50.78	$ 49.71	$ 47.96
Granted, Weighted - Average Exercise Price	42.46	48.00	65.80
Exercised, Weighted - Average Exercise Price	44.51	37.97	44.33
Canceled, Weighted - Average Exercise Price	51.58
Outstanding at end of period, Weighted - Average Exercise Price	50.03	50.78	49.71
Stock options exercisable at end of year, Weighted - Average Exercise Price	$ 50.85	$ 49.79	$ 45.41