Stockholders' Equity (Details 1) (USD $)	12 Months Ended
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices (per share), lower	$ 8.58
Range of exercise prices (per share), upper	$ 74.42
Options outstanding (shares)	1,800,697
Weighted average remaining life in years	7 years 3 months
Weighted average exercise price (per share)	$ 28.78
Options exercisable (shares)	1,127,667
Weighted average exercise price (per share)	$ 20.86
$8.58 – $10.12
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices (per share), lower	$ 8.58
Range of exercise prices (per share), upper	$ 10.12
Options outstanding (shares)	382,047
Weighted average remaining life in years	6 years 0 months 22 days
Weighted average exercise price (per share)	$ 9.98
Options exercisable (shares)	365,174
Weighted average exercise price (per share)	$ 9.98
$10.72 – $13.53
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices (per share), lower	$ 10.72
Range of exercise prices (per share), upper	$ 13.53
Options outstanding (shares)	52,739
Weighted average remaining life in years	7 years 3 months 18 days
Weighted average exercise price (per share)	$ 12.45
Options exercisable (shares)	49,437
Weighted average exercise price (per share)	$ 12.47
$14.47 – $14.47
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices (per share), lower	$ 14.47
Range of exercise prices (per share), upper	$ 14.47
Options outstanding (shares)	427,504
Weighted average remaining life in years	7 years 1 month 10 days
Weighted average exercise price (per share)	$ 14.47
Options exercisable (shares)	273,781
Weighted average exercise price (per share)	$ 14.47
$16.14 – $21.92
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices (per share), lower	$ 16.14
Range of exercise prices (per share), upper	$ 21.92
Options outstanding (shares)	453,177
Weighted average remaining life in years	6 years 11 months 19 days
Weighted average exercise price (per share)	$ 20.79
Options exercisable (shares)	260,375
Weighted average exercise price (per share)	$ 20.05
$32.00 – $74.42
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise prices (per share), lower	$ 32.00
Range of exercise prices (per share), upper	$ 74.42
Options outstanding (shares)	485,230
Weighted average remaining life in years	8 years 6 months 29 days
Weighted average exercise price (per share)	$ 65.42
Options exercisable (shares)	178,900
Weighted average exercise price (per share)	$ 56.34

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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