Stock Incentive Plan - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of authorized stock for stock incentive plan (in shares)	350,000
Stock-based compensation expense	$ 242	$ 196
Shares issued upon exercise of stock options (in shares)	0	1,723
Proceeds from stock option exercises		$ 0
Shares withheld for stock option exercises and related income taxes, amount withheld		$ 49
Options granted (in shares)	0	0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, options, contractual term	10 years
Stock incentive plan vesting period, years	3 years
Stock-based compensation expense	$ 39	$ 32
Cashless Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock option exercises		66
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan vesting period, years	3 years
Stock-based compensation expense	$ 204	$ 164
Restricted stock units granted (in shares)	0	0

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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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Number of shares authorized for issuance under share-based payment arrangement.

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

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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