Stock Option Plan - Changes in Stock Option (Details) (Stock Incentive Plan, Stock Options, USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2014	Dec. 31, 2013
Stock Incentive Plan \| Stock Options
Shares
Outstanding at beginning of period	369,939	370,339
Stock conversion
Granted
Exercised
Forfeited		(400)
Outstanding at end of period	369,939	369,939
Options exercisable at period-end	359,177	359,177
Weighted average exercise price
Outstanding at beginning of period	$ 12.80	$ 12.80
Stock conversion
Granted
Exercised
Forfeited		$ 8.30
Outstanding at end of period	$ 12.80	$ 12.80
Options exercisable at period-end	$ 12.91	$ 12.91
Fair value of options granted

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

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- Definition

Weighted average price at which the stock options conversion made under stock option plan.

+ References

No definition available.

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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://www.xbrl.org/2003/role/presentationRef

-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

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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Subparagraph (c)(1)(iv)(3)

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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

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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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.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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