Stockholders' Equity - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 04, 2018
Equity Class Of Treasury Stock [Line Items]
Stock-based compensation expense	$ 2,100,000	$ 2,000,000.0	$ 10,800,000	$ 9,000,000.0
Additional common shares issued under deferred and stock compensation arrangements			615,412
Treasury stock purchases, shares			846,443
Repurchase of common stock			$ 56,500,000	$ 94,200,000
Long Term Incentive Plan
Equity Class Of Treasury Stock [Line Items]
Treasury stock purchases, shares			10,288
Common Stock Repurchase Plan
Equity Class Of Treasury Stock [Line Items]
Treasury stock purchases, shares			836,155
Stock repurchase programs, remaining authorized amount					$ 484,000,000.0
Stock repurchase programs, authorized amount					$ 500,000,000.0
Repurchase of common stock			$ 300,000,000.0