Stock Incentive Plans (Details 2) - Stock incentive and equity plans [Member]	9 Months Ended
Sep. 30, 2018 $ / shares shares
Shares available for grant
At January 1, 2018	274,494
Granted	(36,953)
Exercised/issued
Cancelled/forfeited	65,902
At September 30, 2018	303,443
Number of options outstanding
At January 1, 2018	125,564
Granted
Exercised/issued
Cancelled/forfeited	(62,919)
At September 30, 2018	62,645
Weighted-average option exercise price
At January 1, 2018 \| $ / shares	$ 19.53
Granted \| $ / shares
Exercised/issued \| $ / shares
Cancelled/forfeited \| $ / shares	32.64
At September 30, 2018 \| $ / shares	$ 12.54
Number of restricted stock and board shares issued
At January 1, 2018	97,692
Granted	1,878
Exercised/issued
Cancelled/forfeited
At September 30, 2018	99,570
Number of restricted stock units outstanding
At January 1, 2018	22,384
Granted	35,075
Exercised/issued	(3,477)
Cancelled/forfeited	(2,983)
At September 30, 2018	50,999

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award number of shares available for grant, cancelled or forfeited.

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Share based compensation arrangement by share based payment award number of shares available for grant, exercised.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

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

Number of non-option equity instruments exercised by participants.

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- Definition

Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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- Definition

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

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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- Definition

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No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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- Definition

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

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No definition available.

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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
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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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- Definition

Number of share instruments newly issued under a share-based compensation plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

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

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 718
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