Stock-Based Compensation - Shares Authorized Under Stock Option Plans by Exercise Price Range (Details)	9 Months Ended
Sep. 30, 2020 $ / shares shares
Number of options, outstanding	838,313
Weighted average remaining contractual life, outstanding options	7 years 7 months 6 days
Number of options, exercisable	669,563
Weighted average remaining contractual life, exercisable options	7 years
Exercise Price Range One [Member]
Exercise price range, lower limit \| $ / shares	$ 0.01
Exercise price range, upper limit \| $ / shares	$ 3.49
Number of options, outstanding	725,313
Weighted average remaining contractual life, outstanding options	8 years 4 months 24 days
Number of options, exercisable	556,563
Weighted average remaining contractual life, exercisable options	8 years
Exercise Price Range Two [Member]
Exercise price range, lower limit \| $ / shares	$ 3.50
Exercise price range, upper limit \| $ / shares	$ 4.99
Number of options, outstanding	64,000
Weighted average remaining contractual life, outstanding options	3 years 7 months 6 days
Number of options, exercisable	64,000
Weighted average remaining contractual life, exercisable options	3 years 7 months 6 days
Exercise Price Range Three [Member]
Exercise price range, lower limit \| $ / shares	$ 5.00
Exercise price range, upper limit \| $ / shares	$ 6.49
Number of options, outstanding
Weighted average remaining contractual life, outstanding options	0 years
Number of options, exercisable
Weighted average remaining contractual life, exercisable options	0 years
Exercise Price Range Four [Member]
Exercise price range, lower limit \| $ / shares	$ 6.50
Exercise price range, upper limit \| $ / shares	$ 7.99
Number of options, outstanding	7,250
Weighted average remaining contractual life, outstanding options	1 year 1 month 6 days
Number of options, exercisable	7,250
Weighted average remaining contractual life, exercisable options	1 year 1 month 6 days
Exercise Price Range Five [Member]
Exercise price range, lower limit \| $ / shares	$ 8.00
Exercise price range, upper limit \| $ / shares	$ 9.99
Number of options, outstanding	2,500
Weighted average remaining contractual life, outstanding options	8 months 12 days
Number of options, exercisable	2,500
Weighted average remaining contractual life, exercisable options	8 months 12 days
Exercise Price Range Six [Member]
Exercise price range, lower limit \| $ / shares	$ 10.00
Exercise price range, upper limit \| $ / shares	$ 19.99
Number of options, outstanding	39,250
Weighted average remaining contractual life, outstanding options	3 months 19 days
Number of options, exercisable	39,250
Weighted average remaining contractual life, exercisable options	3 months 19 days

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(iii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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