Stock Based Compensation - Options Outstanding (Details) - $ / shares	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Number of Shares Underlying Options
Options outstanding, beginning (in shares)	118,003
Expired (in shares)	(440)
Forfeited (in shares)	(10,038)
Options outstanding, ending (in shares)	107,525.000
Weighted Average Exercise Price
Options outstanding, beginning (in dollars per share)	$ 19.90
Expired (in dollars per share)	13.18
Forfeited (in dollars per share)	22.79
Options outstanding, ending (in dollars per share)	$ 19.64
Number of Shares Underlying Options/Weighted Average Exercise Price
Exercisable, Number of Shares Underlying Options (in shares)	107,525	118,003
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 19.64	$ 19.90

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- Definition

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.

+ References

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)
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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
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- Definition

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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No definition available.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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