Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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

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

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Purchase price of common stock expressed as a percentage of its fair value.

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Stock-based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2013	Dec. 31, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense	$ 131,000	$ 358,000
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation shares authorized under stock option plans		770,000
Percent of the fair value options granted		100.00%
'Shares available for future grant		0
Weighted average remaining contractual term stock options outstanding	2 years 5 months 26 days
Weighted average remaining contractual life for options exercisable	2 years 5 months 26 days
2005 Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		5 years
Stock options, when granted, expiration period		10 years
2010 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation shares authorized under stock option plans	0		2,500,000	1,350,000
Percent of the fair value options granted	100.00%
Weighted average remaining contractual term stock options outstanding	3 years 3 days
Weighted average remaining contractual life for options exercisable	3 years 3 days
Number of options outstanding, Granted	0	0
Unrecognized compensation costs related to unvested stock options	$ 235,000
Unrecognized compensation costs weighted average period	6 months 7 days
2010 Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	5 years
Stock options, when granted, expiration period	10 years
2010 Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock awards granted	0