Stock Compensation Plans - Stock-Based Compensation Expense Included in Consolidated Statement of Income and Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 38,610	$ 31,918	$ 32,581
Less tax benefit	(7,305)	(6,556)	(5,659)
Total stock-based compensation, net of tax	31,305	25,362	26,922
Equity-based awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	34,482	29,401	26,567
Liability-based awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 4,128	$ 2,517	$ 6,014

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

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