Stock-Based Compensation - Shares Issued in Connection with Stock Compensation Awards (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Arrangement [Abstract]
New shares issued from available authorized shares	0	0
Issued from available treasury stock	66,215	100,865
Total	66,215	100,865
Proceeds from stock option exercises	$ 1,463	$ 4,885

Treasury Shares Issued Related To Stock Option Exercises

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- References

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Number of shares issued under share-based payment arrangement.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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