Stock Compensation Plans - Stock-Based Compensation Expense and Related Tax Benefits (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 13,494	$ 12,757	$ 21,479	$ 21,091
Less: Tax benefit	(2,568)	(2,141)	(3,962)	(3,523)
Total stock-based compensation expense, after tax	10,926	10,616	17,517	17,568
Equity-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	10,358	10,696	18,982	18,300
Liability-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 3,136	$ 2,061	$ 2,497	$ 2,791

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

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-Name Accounting Standards Codification
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