Debt Maturities of Long Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Long-term Debt, Fiscal Year Maturity [Abstract]
Final Maturity Balances - First Year	$ 10,000	$ 10,000
Final Maturity Balances - Second Year	10,000	10,000
Final Maturity Balances - Third Year	10,000	10,000
Final Maturity Balances - Fourth Year	0	10,000
Final Maturity Balances - Fifth Year	0	0
Final Maturity Balances - Years After	0	0
Final Maturity Balances - Total	$ 30,000	$ 40,000
Final Maturity Weighted Average Rate - First Year	1.65%	4.70%
Final Maturity Weighted Average Rate - Second Year	1.43%	1.65%
Final Maturity Weighted Average Rate - Third Year	3.88%	1.43%
Final Maturity Weighted Average Rate - Fourth Year	0.00%	3.88%
Final Maturity Weighted Average Rate - Fifth Year	0.00%	0.00%
Final Maturity Weighted Average Rate - Years After	0.00%	0.00%
Final Maturity Weighted Average Rate - Total	2.32%	2.92%

Weighted Average Rate of Repayments of Principal after Year Five

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Weighted Average Rate of Repayments of Long Term Debt Principal in the Next Twelve Months

+ References

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Weighted Average Rate of Repayments of Long-Term Debt Principal in Year Five

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- Definition

Weighted Average Rate of Repayments of Long Term Debt Principal in Year Four

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- Definition

Weighted Average Rate of Repayments of Long-Term Debt Principal in Year Three

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Weighted Average Rate of Repayments of Long-Term Debt Principal in Year Two

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- Definition

Weighted Average Rate of Total Long Term Debt Principal Repayments

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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-Name Regulation S-X (SX)

-Number 210

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-Article 7

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-Name Regulation S-X (SX)

-Number 210

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-Paragraph 20, 22

-Article 5

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-Name Accounting Standards Codification

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-SubTopic 10

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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