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

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

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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		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2013	Dec. 31, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense	$ 189,000	$ 167,000	$ 905,000	$ 606,000
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation shares authorized under stock option plans	770,000		770,000
Percent of the fair value options granted			100.00%
Shares available for grant	0		0
Weighted average remaining contractual term stock options outstanding			2 years 9 months 7 days
Weighted average remaining contractual life for options exercisable			2 years 9 months 7 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	95,427		95,427		2,500,000	1,350,000
Percent of the fair value options granted			100.00%
Weighted average remaining contractual term stock options outstanding			2 years 7 months 2 days
Weighted average remaining contractual life for options exercisable			2 years 3 months 18 days
Number of options outstanding, Granted			0	0
Unrecognized compensation costs related to unvested stock options	$ 1,900,000		$ 1,900,000
Unrecognized compensation costs weighted average period			1 year 2 months 12 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]
Vesting period			3 years	3 years
Restricted stock awards granted			3,000	148,000
Weighted average fair value of Restricted shares granted			$ 8.15	$ 12.7