Employee Benefit Plans - Options Outstanding by Exercise Price Range (Details) - Officer and Employee Plans [Member] - $ / shares	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Prices (in dollars per share)	$ 10.18	$ 10.29
Number Outstanding (in shares)	105,315	136,658
Options Outstanding, Weighted Average Remaining Life	2 years 9 months 21 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 10.18
Options Exercisable, Number Exercisable (in shares)	105,315
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 10.18
6.60 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Prices (in dollars per share)	$ 6.60
Number Outstanding (in shares)	20,000
Options Outstanding, Weighted Average Remaining Life	1 year 5 months 12 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 6.60
Options Exercisable, Number Exercisable (in shares)	20,000
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 6.60
6.80 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Prices (in dollars per share)	$ 6.80
Number Outstanding (in shares)	13,250
Options Outstanding, Weighted Average Remaining Life	5 months 1 day
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 6.80
Options Exercisable, Number Exercisable (in shares)	13,250
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 6.80
9.48 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Prices (in dollars per share)	$ 9.48
Number Outstanding (in shares)	18,500
Options Outstanding, Weighted Average Remaining Life	2 years 5 months 12 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 9.48
Options Exercisable, Number Exercisable (in shares)	18,500
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 9.48
9.60 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Prices (in dollars per share)	$ 9.60
Number Outstanding (in shares)	22,750
Options Outstanding, Weighted Average Remaining Life	3 years 3 months
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 9.60
Options Exercisable, Number Exercisable (in shares)	22,750
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 9.60
11.67 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Prices (in dollars per share)	$ 11.76
Number Outstanding (in shares)	2,266
Options Outstanding, Weighted Average Remaining Life	1 year 9 months
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 11.76
Options Exercisable, Number Exercisable (in shares)	2,266
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 11.76
15.05 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Prices (in dollars per share)	$ 15.05
Number Outstanding (in shares)	28,549
Options Outstanding, Weighted Average Remaining Life	4 years 9 months 29 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 15.05
Options Exercisable, Number Exercisable (in shares)	28,549
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 15.05

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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