Stock Compensation Plans - Stock-Based Compensation Expense and Related Tax Benefits (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 12,757	$ 7,796	$ 21,091	$ 15,571
Less: Tax benefit	(2,141)	(1,335)	(3,523)	(2,898)
Total stock-based compensation expense, after tax	10,616	6,461	17,568	12,673
Equity-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	10,696	7,554	18,300	15,174
Liability-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 2,061	$ 242	$ 2,791	$ 397

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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