Summary of Significant Accounting Policies - Taxes and Retirement Plan (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes
Unrecognized tax benefit	$ 0us-gaap_UnrecognizedTaxBenefits	$ 0us-gaap_UnrecognizedTaxBenefits
Retirement Plan
Pension asset	502,000	965,000
Net (loss) gain recognized in other comprehensive income	$ (1,400,000)	$ 597,000	$ (24,000)

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This represents the entire assets recognized in the balance sheet that are associated with the defined benefit plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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-URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.10)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Details

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- Definition

Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (i-k)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

+ Details

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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