Stock-based Payments and Director Fees - Schedule of Restricted Stock Plans (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
Jul. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining contractual terms			2 months 12 days
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares granted (in shares)		308,334	233,834	198,000
Total expected cost of grant		$ 4,217	$ 3,178	$ 2,715
Shares granted during the year (in shares)		79,000	48,500	39,000
Grant expense recognized for the year		$ 839	$ 1,026	$ 765
Shares, nonvested (in shares)		114,334	116,389	138,333
Per share grant fair value (in dollars per share)		$ 13.87	$ 13.62	$ 13.83
Shares, fully vested (in shares)		194,000	117,445	59,667
Per share grant date fair value (in dollars per share)		$ 13.56	$ 13.55	$ 13.69
Restricted stock \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted during the year (in shares)			3,000
Vesting period			1 year
Restricted stock \| Directors' Grants \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares granted (in shares)		12,000	12,000	10,000
Total expected cost of grant		$ 162	$ 162	$ 146
Shares granted during the year (in shares)		0	12,000	0
Grant expense recognized for the year		$ 0	$ 148	$ 14
Shares, nonvested (in shares)		0	6,000	0
Per share grant fair value (in dollars per share)		$ 13.48	$ 13.48	$ 0
Shares, fully vested (in shares)		12,000	6,000	10,000
Per share grant date fair value (in dollars per share)		$ 13.48	$ 13.48	$ 14.61
Vesting period		1 year
Restricted stock \| Employee and Service Provider Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares granted (in shares)		144,667	146,334	149,000
Total expected cost of grant		$ 1,953	$ 1,976	$ 2,027
Shares granted during the year (in shares)		0	0	0
Grant expense recognized for the year		$ 367	$ 629	$ 675
Shares, nonvested (in shares)		0	47,889	99,333
Per share grant fair value (in dollars per share)		$ 13.50	$ 13.50	$ 13.50
Shares, fully vested (in shares)		144,667	98,445	49,667
Per share grant date fair value (in dollars per share)		$ 13.50	$ 13.50	$ 13.50
Weighted average remaining contractual terms			7 months 6 days	1 year 7 months 6 days
Restricted stock \| Employee And Service Provider Grants Second Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares granted (in shares)		38,667	39,000	39,000
Total expected cost of grant		$ 539	$ 544	$ 542
Shares granted during the year (in shares)		0	0	39,000
Grant expense recognized for the year		$ 170	$ 180	$ 76
Shares, nonvested (in shares)		12,667	26,000	39,000
Per share grant fair value (in dollars per share)		$ 13.95	$ 13.95	$ 13.95
Shares, fully vested (in shares)		26,000	13,000	0
Per share grant date fair value (in dollars per share)		$ 13.95	$ 13.95	$ 0
Weighted average remaining contractual terms		7 months 6 days	1 year 7 months 6 days	2 years 7 months 6 days
Restricted stock \| Employee And Service Provider Grants Third Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares granted (in shares)	36,500	34,000	36,500
Total expected cost of grant		$ 462	$ 496
Shares granted during the year (in shares)		0	36,500
Grant expense recognized for the year		$ 149	$ 69
Shares, nonvested (in shares)		22,667	36,500
Per share grant fair value (in dollars per share)		$ 13.58	$ 13.58
Shares, fully vested (in shares)		11,333	0
Per share grant date fair value (in dollars per share)		$ 13.58	$ 0
Weighted average remaining contractual terms		1 year 7 months 6 days	2 years 7 months 6 days
Restricted stock \| Employee and Service Provider Grants Fourth Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares granted (in shares)		79,000
Total expected cost of grant		$ 1,101
Shares granted during the year (in shares)		79,000
Grant expense recognized for the year		$ 153
Shares, nonvested (in shares)		79,000
Per share grant fair value (in dollars per share)		$ 13.94
Shares, fully vested (in shares)		0
Per share grant date fair value (in dollars per share)		$ 0
Weighted average remaining contractual terms		2 years 7 months 6 days

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The weighted average fair value of vested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Net number of non-option equity instruments granted to participants.

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