Stock-Based Compensation - Narrative (Details) - shares	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stock options and assumed options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised (in shares)	194,443	113,159	258,191	198,625
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted (in shares)	218,344	146,766	319,072	337,016
Restricted stock units vested (in shares)	64,075	118,606	87,123	162,066
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)	136,650	102,500	141,650	110,500

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.

+ References

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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.

+ 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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