Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Restricted Stock, Stock Options and Other Stock Plans - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining contractual term of unexercised stock options	8 years
Unrecognized compensation cost related to stock options and restricted stock awards	$ 1.8		$ 0.6
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued by the company	0	94,431
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued by the company	630,352	57,788