Stock-Based Compensation (Details 3) (USD $)	12 Months Ended
Dec. 31, 2012
Options Outstanding
Number Of Options (in shares)	1,432,228
Weighted-Average Exercise Price (in dollars per share)	$ 10.34
Weighted-Average Remaining Contractual Term	5 years 1 month 6 days
Options Exercisable
Number Of Options (in shares)	1,179,959
Weighted-Average Exercise Price (in dollars per share)	$ 8.49
Exercise Price Ranges, $3.65-$9.00
Stock options outstanding
Exercise price, low end of range (in dollars per share)	$ 3.65
Exercise price, high end of range (in dollars per share)	$ 9.00
Options Outstanding
Number Of Options (in shares)	643,361
Weighted-Average Exercise Price (in dollars per share)	$ 3.69
Weighted-Average Remaining Contractual Term	3 years 6 months
Options Exercisable
Number Of Options (in shares)	643,361
Weighted-Average Exercise Price (in dollars per share)	$ 3.69
Exercise Price Ranges, $9.01-$18.00
Stock options outstanding
Exercise price, low end of range (in dollars per share)	$ 9.01
Exercise price, high end of range (in dollars per share)	$ 18.00
Options Outstanding
Number Of Options (in shares)	677,609
Weighted-Average Exercise Price (in dollars per share)	$ 14.56
Weighted-Average Remaining Contractual Term	6 years 2 months 12 days
Options Exercisable
Number Of Options (in shares)	501,696
Weighted-Average Exercise Price (in dollars per share)	$ 13.55
Exercise Price Ranges, $18.01-$24.18
Stock options outstanding
Exercise price, low end of range (in dollars per share)	$ 18.01
Exercise price, high end of range (in dollars per share)	$ 24.18
Options Outstanding
Number Of Options (in shares)	111,258
Weighted-Average Exercise Price (in dollars per share)	$ 23.17
Weighted-Average Remaining Contractual Term	8 years 4 months 24 days
Options Exercisable
Number Of Options (in shares)	34,902
Weighted-Average Exercise Price (in dollars per share)	$ 24.18

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- Definition

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

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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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c)

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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.

+ References

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

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-Name Accounting Standards Codification

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

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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.

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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.

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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.

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