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Stockholders' Equity - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 04, 2018
Equity Class Of Treasury Stock [Line Items]
Stock-based compensation expense	$ 6,800,000	$ 5,700,000
Additional common shares issued under deferred and stock compensation arrangements	603,052
Long Term Incentive Plan
Equity Class Of Treasury Stock [Line Items]
Treasury stock purchases, shares	15,631
Common Stock Repurchase Plan
Equity Class Of Treasury Stock [Line Items]
Treasury stock purchases, shares	0
Stock repurchase programs, remaining authorized amount			$ 390,000,000.0
Stock repurchase programs, authorized amount			$ 500,000,000.0