Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 24.3	$ 14.0
Unamortized compensation expense expected to be vested	61.7
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	1.3
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	10.8
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	3.7
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 7.9
Award vesting period (in years)	3 years
Performance Shares \| Scenario Forecast
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of incentive stock awards expected to be vested and awarded of stocks granted (as a percent)			103.00%	105.00%	107.00%
Performance Shares \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of incentive stock awards expected to be vested and awarded of stocks granted (as a percent)	0.00%
Performance Shares \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of incentive stock awards expected to be vested and awarded of stocks granted (as a percent)	200.00%
2011 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant (in shares)	3,800,000
2011 Plan \| Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period (in years)	4 years
Plan term (in years)	10 years
2011 Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period (in years)	4 years
Directors Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 0.6
Directors Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period (in years)	1 year
2000 Plan \| Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period (in years)	3 years