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=6415400&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=6415400&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=6415400&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=6415400&loc=d3e5070-113901

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Stock-Based Compensation - Summary of Stock Options Outstanding and Exercisable by Stock Option Plan (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Outstanding Options, Number of Options Outstanding	158,248	160,748	309,479	309,479
Outstanding Options, Weighted Average Exercise Price	$ 25.06	$ 19.75	$ 19.75	$ 19.75
Options Exercisable, Number of Options Exercisable	132,417		256,656
Options Exercisable, Weighted Average Exercise Price	$ 29.25		$ 23.04
1995 Stock Incentive Plan [Member]
Outstanding Options, Number of Options Outstanding	8,750
Outstanding Options, Weighted Average Exercise Price	$ 31.20
Options Exercisable, Number of Options Exercisable	8,750
Options Exercisable, Weighted Average Exercise Price	$ 31.20
2004 Stock Incentive Plan [Member]
Outstanding Options, Number of Options Outstanding	69,500
Outstanding Options, Weighted Average Exercise Price	$ 10.10
Options Exercisable, Number of Options Exercisable	51,167
Options Exercisable, Weighted Average Exercise Price	$ 12.74
2004 Director's Plan [Member]
Outstanding Options, Number of Options Outstanding	74,998
Outstanding Options, Weighted Average Exercise Price	$ 39.68
Options Exercisable, Number of Options Exercisable	71,250
Options Exercisable, Weighted Average Exercise Price	$ 41.32
2013 Omnibus Incentive Plan [Member]
Outstanding Options, Number of Options Outstanding	5,000
Outstanding Options, Weighted Average Exercise Price	$ 2.99
Options Exercisable, Number of Options Exercisable	1,250
Options Exercisable, Weighted Average Exercise Price	$ 2.99