Stock-Based Compensation - Narrative (Details) - shares	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock options and assumed options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised (in shares)	63,083	194,443	136,258	258,191
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted (in shares)	428,194	218,344	555,410	319,072
Restricted stock units vested (in shares)	173,553	64,075	262,923	87,123
Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted (in shares)	120,314	0	120,314	0
Restricted stock units vested (in shares)	0	0	20,000	0
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)	133,700	136,650	133,700	141,650

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

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No definition available.

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

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