Stockholders' Equity - Restricted Stock and Restricted Stock Units (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Restricted Stock
Restricted Stock and Restricted Stock Units
Number of shares issued (shares)	156,184	123,564
Value of shares issued	$ 512,300	$ 611,600
Weighted average estimated fair value	$ 3.28	$ 4.95
Restricted Stock \| Minimum
Restricted Stock and Restricted Stock Units
Vesting terms (in years)	1 year
Restricted Stock \| Maximum
Restricted Stock and Restricted Stock Units
Vesting terms (in years)	4 years
Restricted Stock Units
Restricted Stock and Restricted Stock Units
Number of shares issued (shares)	325,853	184,454
Value of shares issued	$ 863,000.0	$ 908,600
Weighted average estimated fair value	$ 2.65	$ 4.93
Vesting terms (in years)	1 year

Restricted Stock And Restricted Stock Units Issued [Abstract]

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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.

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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).

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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