Fair Value Measurement (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost	$ 39,014	$ 46,146
Unrealized Gains	0	8
Unrealized Losses	(25)	0
Fair value	38,988	46,154
Cash and cash equivalents	19,173	19,661
Investments Available for Sale	19,815	26,493
Unobservable input reconciliation [Roll Forward]
Balance at beginning of period	4,172	4,699	14,364
Gain (losses) included in losses	(1,608)	927	5,595
Settlements	0	(1,454)	(15,260)
Balance at end of period	2,564	4,172	4,699
Minimum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Matutiries of available for sale securities	1 year
Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Matutiries of available for sale securities	2 years
Cash [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost	11,699	19,661
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair value	11,699	19,661
Cash and cash equivalents	11,699	19,661
Investments Available for Sale	0	0
Series I Warrants [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Series I warrants	2,564	4,172
Fair value inputs [Abstract]
Exercise price per common share (in dollars per share)	$ 3.59	$ 3.59
Common share price (in dollars per share)	$ 19.41	$ 29.28
Discount rate (in hundredths)	1.75%	0.72%
Volatility rate (in hundredths)	91.55%	94.15%
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost	27,315	26,485
Unrealized Gains	0	8
Unrealized Losses	(25)	0
Fair value	27,289	26,493
Cash and cash equivalents	7,474	0
Investments Available for Sale	19,815	26,493
Level 1 [Member] \| Certificates of Deposit [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost		17,836
Unrealized Gains		0
Unrealized Losses		0
Fair value		17,836
Cash and cash equivalents		0
Investments Available for Sale		17,836
Level 1 [Member] \| Mutual Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost	73
Unrealized Gains	0
Unrealized Losses	0
Fair value	73
Cash and cash equivalents	73
Investments Available for Sale	0
Level 1 [Member] \| Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost	10,782	8,649
Unrealized Gains	0	8
Unrealized Losses	0	0
Fair value	10,782	8,657
Cash and cash equivalents	2,325	0
Investments Available for Sale	8,457	8,657
Level 1 [Member] \| Municipal Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost	2,173
Unrealized Gains	0
Unrealized Losses	0
Fair value	2,173
Cash and cash equivalents	665
Investments Available for Sale	1,508
Level 1 [Member] \| US Agency Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Adjustment Cost	14,287
Unrealized Gains	0
Unrealized Losses	(25)
Fair value	14,262
Cash and cash equivalents	4,411
Investments Available for Sale	9,851
Level 1 [Member] \| Series I Warrants [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Series I warrants	0	0
Level 2 [Member] \| Series I Warrants [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Series I warrants	0	0
Level 3 [Member] \| Series I Warrants [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Series I warrants	$ 2,564	$ 4,172

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ 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 210.5-02.2)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 19

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

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- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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This item represents the gross unrealized losses for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

+ 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

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-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 7

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- Definition

The exercise price of each class of warrants or rights outstanding.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(4))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Subparagraph 4

-Article 4

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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- Definition

Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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-Name Accounting Standards Codification

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-SubTopic 10

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-Paragraph 2

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- Definition

Settlements that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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- Definition

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

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- Definition

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No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

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- Definition

Period of maturity of a debt security categorized as neither trading nor held-to-maturity, in PnYnMnDTn.

+ References

No definition available.

+ Details

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