Equity Plans - Restricted Stock Units - (Details)	12 Months Ended
Dec. 31, 2020 installment $ / shares shares	Dec. 31, 2018 installment
Equity Plans
Restricted stock units vesting, number of equal installments \| installment	4
Restricted stock unit incentive awards granted in 2018
Equity Plans
Restricted stock units vesting, number of equal installments \| installment		3
Vesting period		18 months
Number of Shares
Number of shares, Unvested, Beginning balance \| shares	278,482
Number of shares, Granted \| shares	142,000
Number of shares, Vested \| shares	(131,147)
Number of Shares, Forfeited \| shares	(44,790)
Number of shares, Unvested, Ending balance \| shares	244,545
Weighted-Average Grant Date Fair Value
Weighted-Average Grant Date Fair Value, Unvested, Beginning balance \| $ / shares	$ 10.08
Weighted-Average Grant Date Fair Value, Granted \| $ / shares	7.80
Weighted-Average Grant Date Fair Value, Vested \| $ / shares	9.52
Weighted-Average Grant Date Fair Value, Forfeited \| $ / shares	8.67
Weighted-Average Grant Date Fair Value, Unvested, Ending balance \| $ / shares	$ 9.31

The number of equal installments established for the restricted stock units vesting schedule.

No definition available.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
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- Definition

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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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No definition available.

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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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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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.

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