The expected life of employee stock purchase plans.

No definition available.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

Amount of noncash expense for 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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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 567	$ 762	$ 1,013	$ 1,447
Stock options granted	0		0
Expected life			6 months
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options exercised (in shares)	0	0	0	0
Unrecognized compensation cost related to options	$ 117		$ 117
Share-based compensation, weighted average recognized period			1 year 9 months 18 days
RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, weighted average recognized period			2 years 2 months 12 days
Unrecognized compensation cost related to RSUs	$ 2,584		$ 2,584