Financial Instruments (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Financial Instruments (Additional Textual) [Abstract]
Transfers of assets between fair value hierarchy levels	$ 0	$ 0
Fair Value Measurements, Recurring \| Level 1 \| Money Market Funds
Financial Instruments (Textual) [Abstract]
Cash equivalents consisting of money market funds	15,300,000	16,500,000
Fair Value Measurements, Recurring \| Fair Value, Inputs, Level 2
Financial Instruments (Additional Textual) [Abstract]
Fair value of assets	0
Fair value liabilities	0
Fair Value Measurements, Recurring \| Fair Value, Inputs, Level 3
Financial Instruments (Additional Textual) [Abstract]
Fair value of assets	0
Fair value liabilities	$ 0

Fair value assets between hierarchy levels transfers amount.

No definition available.

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- Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

+ Details

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