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://www.xbrl.org/2003/role/presentationRef
-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=96867065&loc=d3e5070-113901

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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 outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Stock Based Compensation - Summary of Stock Options Outstanding and Exercisable by Stock Option Plan (Details) - $ / shares	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Outstanding Stock Options, Number of Options Outstanding	105,245	110,828	321,700	326,424
Outstanding Stock Options, Weighted Average Exercise Price	$ 18.62	$ 18.24	$ 18.82	$ 24.90
Exercisable Stock Options Exercisable, Number of Options Exercisable	105,139		321,491
Exercisable Stock Options Exercisable, Weighted Average Exercise Price	$ 18.60		$ 18.81
2004 Plan [Member]
Outstanding Stock Options, Number of Options Outstanding	4,792
Outstanding Stock Options, Weighted Average Exercise Price	$ 35.14
Exercisable Stock Options Exercisable, Number of Options Exercisable	4,792
Exercisable Stock Options Exercisable, Weighted Average Exercise Price	$ 35.14
2004 Director's Plan [Member]
Outstanding Stock Options, Number of Options Outstanding	1,390
Outstanding Stock Options, Weighted Average Exercise Price	$ 629.52
Exercisable Stock Options Exercisable, Number of Options Exercisable	1,390
Exercisable Stock Options Exercisable, Weighted Average Exercise Price	$ 629.52
2013 Plan [Member]
Outstanding Stock Options, Number of Options Outstanding	417
Outstanding Stock Options, Weighted Average Exercise Price	$ 35.88
Exercisable Stock Options Exercisable, Number of Options Exercisable	312
Exercisable Stock Options Exercisable, Weighted Average Exercise Price	$ 35.88
Replacement Stock Options [Member]
Outstanding Stock Options, Number of Options Outstanding	98,646
Outstanding Stock Options, Weighted Average Exercise Price	$ 9.13
Exercisable Stock Options Exercisable, Number of Options Exercisable	98,645
Exercisable Stock Options Exercisable, Weighted Average Exercise Price	$ 9.23