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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, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anti-dilutive weighted average stock options excluded from computation of earnings per share	4,300,000	7,300,000	6,600,000	8,200,000
Unrecognized compensation cost related to unvested options and restricted stock	$ 140,600		$ 140,600
Stock options granted during period			2,456,015
Weighted-average grant date fair value, per share			$ 30.40
Compensation cost recognized			$ 52,167	$ 50,645
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	14,900	$ 14,200	45,400	46,700
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	$ 2,300	$ 1,400	$ 6,000	$ 3,100
Unrecognized compensation cost vesting period	2 years 8 months 12 days
Restricted shares granted during period			145,076,000
Weighted-average grant date fair value, per share			$ 133.98
Unvested Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost vesting period	2 years 8 months 12 days