Margin Account Loan (Details) (USD $)	3 Months Ended
Mar. 31, 2014
Margin Account Loan [Abstract]
Line of credit facility initiation date	Jul. 26, 2011
Interest rate during period (percent)	2.50%
Reduction in Wells Fargo base rate (percent)	2.75%
Margin account loan liability	$ 0
Increase in accrued interest	$ 130,000

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A loan collateralized by marketable securities which requires the value of these securities remain above the outstanding loan balance. A drop in the value of these marketable securities below the outstanding loan balance would trigger a margin call. The margin call would require that the difference between the outstanding loan balance and the value of the securities be either paid down or the collateral increased, proportionally.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Reduction in Wells Fargo Base Rate, Percentage

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Increase for accrued, but unpaid interest on the credit facility for the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

+ 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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Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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