Summary of Stock Options Outstanding and Exercisable (Details) (USD $)	12 Months Ended
Dec. 31, 2014
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Outstanding number of Options	1,068,515
Outstanding Average Life	8 years 3 months
Outstanding Average Exercise Price	$ 2.89
Exercisable number of Options	494,291
Exercisable, Weighted Average Exercise Price	$ 4.38
$0.36-$1.33
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Price Range, Minimum	$ 0.36
Price Range, Maximum	$ 1.33
Outstanding number of Options	29,933
Outstanding Average Life	9 years 9 months
Outstanding Average Exercise Price	$ 1.05
Exercisable number of Options	704
Exercisable, Weighted Average Exercise Price	$ 1.08
$1.38-$1.38
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Price Range, Minimum	$ 1.38
Price Range, Maximum	$ 1.38
Outstanding number of Options	727,869
Outstanding Average Life	8 years 5 months 19 days
Outstanding Average Exercise Price	$ 1.38
Exercisable number of Options	329,189
Exercisable, Weighted Average Exercise Price	$ 1.38
$1.40-$1.95
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Price Range, Minimum	$ 1.40
Price Range, Maximum	$ 1.95
Outstanding number of Options	212,495
Outstanding Average Life	9 years 1 month 10 days
Outstanding Average Exercise Price	$ 1.89
Exercisable number of Options	70,410
Exercisable, Weighted Average Exercise Price	$ 1.84
$1.96-$22.98
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Price Range, Minimum	$ 1.96
Price Range, Maximum	$ 22.98
Outstanding number of Options	82,300
Outstanding Average Life	4 years 5 months 9 days
Outstanding Average Exercise Price	$ 13.68
Exercisable number of Options	78,070
Exercisable, Weighted Average Exercise Price	$ 13.55
$22.99-$33.42
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Price Range, Minimum	$ 22.99
Price Range, Maximum	$ 33.42
Outstanding number of Options	15,918
Outstanding Average Life	3 years 8 months 27 days
Outstanding Average Exercise Price	$ 32.87
Exercisable number of Options	15,918
Exercisable, Weighted Average Exercise Price	$ 32.87

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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-Publisher FASB

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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