Stock-Based Compensation - Narrative (Details) - shares	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Stock options and assumed options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised (in shares)	139,225	60,043	397,416	258,668
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted (in shares)	169,699	88,308	488,771	425,324
Restricted stock units vested (in shares)	34,136	15,880	121,259	177,946
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)	2,000	30,000	143,650	140,500

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.

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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.

+ References

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