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Earnings Per Share - (Additional Information) (Detail) - USD ($)		1 Months Ended	3 Months Ended
	Jul. 22, 2019	Sep. 23, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Jul. 31, 2019	Jul. 19, 2019	Jul. 16, 2019
Stock options, outstanding			915,518	1,027,831	957,559
Stock options, weighted average exercise price			$ 32.91	$ 28.53	$ 30.81
Common stock excluded from calculation of diluted earnings per share			39,711	210,388
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					$ 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			716,630	680,549	734,984