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Earnings Per Share - (Additional Information) (Detail) - USD ($)		1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 22, 2019	Sep. 23, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Jul. 31, 2019	Jul. 19, 2019	Jul. 16, 2019
Stock options, outstanding			723,914	959,916	723,914	959,916	957,559
Stock options, weighted average exercise price			$ 41.03	$ 30.44	$ 41.03	$ 30.44	$ 30.81
Common stock excluded from calculation of diluted earnings per share			60,202	47,705	117,160	85,503
Common Stock [Member]
Conversion of Convertible Securities Stock Issued			2,316,200
2.125% Convertible Senior Notes due 2021
Aggregate principal amount			$ 115,000,000.0		$ 115,000,000.0					$ 92,000,000.0
2.125% Convertible Senior Notes due 2021 \| Common Stock [Member]
Conversion of Convertible Securities Stock Issued	1,850,155	466,045
0.375% Convertible Senior Notes due 2024
Aggregate principal amount								$ 287,500,000	$ 287,500,000
Restricted Stock Units and Performance Stock Units
Restricted stock units, outstanding			675,567	740,213	675,567	740,213	734,984