Stock Based Compensation (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) item shares	Mar. 31, 2020 USD ($) shares
Stock-based compensation
Number of stock-based employee compensation plans \| item	4
Number of executive stock award plans \| item	3
Outstanding stock options (in shares)	0	0
Stock options exercised (in shares)	0
Total unrecognized compensation cost related to non-vested share-based compensation arrangements \| $	$ 9,170
Weighted-average period over which unrecognized compensation cost is expected to be recognized	3 years 7 months 6 days
Stock options
Stock-based compensation
Total fair value of options vested and expensed \| $	$ 0	$ 0
Outstanding stock options (in shares)	0
Stock options exercised (in shares)		0

Represents the number of active executive stock award plans.

No definition available.

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- Definition

Represents the number of active stock-based employee compensation plans.

+ References

No definition available.

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- Definition

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

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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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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.

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

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

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