Short Term Borrowings (Details Narrative) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Lines Of Credit Facility
Established Lines	$ 60,000
Maximum Amount Outstanding	27,500
Weighted average daily amounts of borrowings outstanding	$ 27,900	$ 23,800
Weighted average interest rates on line of credit facility (As a percentage)	1.40%	1.31%
Weighted Average Interest Rate	1.39%

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Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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- Definition

The effective interest rate at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

+ Details

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- Definition

Maximum month-end amount borrowed under the credit facility during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Industry Guide

-Number 3

-Section VII

-Subsection 2

+ Details

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