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Earnings Per Share Data ("EPS") and Stock Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anti-dilutive weighted average stock options excluded from computation of earnings per share	7,100,000	4,300,000	6,700,000	6,600,000
Unrecognized compensation cost related to unvested options and restricted stock	$ 113,600		$ 113,600
Stock options granted during period			2,586,966
Weighted-average grant date fair value, per share			$ 14.57
Compensation cost recognized			$ 49,928	$ 52,167
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	13,000	$ 14,900	41,600	45,400
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	$ 2,500	$ 2,300	$ 7,300	$ 6,000
Unrecognized compensation cost vesting period			2 years 4 months 24 days
Restricted shares and restricted units granted during period			128,467
Weighted-average grant date fair value, per share			$ 69.03
Unvested Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost vesting period			2 years 4 months 24 days