Provision for Federal and Foreign Income Tax Expense for Continuing Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income before income taxes, U.S.	$ 289,727	$ 280,535	$ 274,756
Income before income taxes, Foreign	21,007	64,842	85,890
Income before income taxes	$ 310,734	$ 345,377	$ 360,646

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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-Name Accounting Standards Codification
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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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