Stock-Based Compensation - Narrative (Details) - shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Stock options and assumed options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised (in shares)	73,175	63,748
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted (in shares)	127,216	100,728
Restricted stock units vested (in shares)	89,370	23,048
2015 Equity Incentive Plan \| Stock options and assumed options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	0	5,000

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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- Definition

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

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

+ References

No definition available.

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- Definition

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

+ References

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