Shareholders' Equity - Additional Information (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Common stock, shares authorized	100,000,000.0	100,000,000.0
Common stock, par value	$ 0.01	$ 0.01
Common stock reserved for issuance under stock-based award plans	1,400,000
Stock Repurchased During Period, Shares	200,000	400,000	500,000
Common stock remaining under repurchase authorization	13,500,000
Maximum
Class of Stock [Line Items]
Stock repurchase program, shares authorized to be repurchased	20,000,000.0