Equity Incentive Plans (Details 3) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Exercise prices and related information of stock option outstanding
Options outstanding, Number outstanding	1,198
Options outstanding, Wtd. Avg. remaining contractual life	6 years 10 months 6 days
Options outstanding, Wtd. Avg. exercise price	$ 18.92
Options exercisable, Number exercisable	722
Options exercisable Wtd. Avg. Remaining Contractual Life	5 years 11 months 12 days
Options exercisable, Wtd. Avg. exercise price	$ 17.51
3.17 - 5.26 [Member]
Exercise prices and related information of stock option outstanding
Lower range limit, Exercise price	$ 3,170
Upper range limit, Exercise price	$ 5.26
Options outstanding, Number outstanding	29
Options outstanding, Wtd. Avg. remaining contractual life	1 year
Options outstanding, Wtd. Avg. exercise price	$ 4.55
Options exercisable, Number exercisable	30
Options exercisable Wtd. Avg. Remaining Contractual Life	1 year
Options exercisable, Wtd. Avg. exercise price	$ 4.55
6.66 - 13.72 [Member]
Exercise prices and related information of stock option outstanding
Lower range limit, Exercise price	$ 6,660
Upper range limit, Exercise price	$ 13,720.00
Options outstanding, Number outstanding	46
Options outstanding, Wtd. Avg. remaining contractual life	2 years 5 months 1 day
Options outstanding, Wtd. Avg. exercise price	$ 9.15
Options exercisable, Number exercisable	45
Options exercisable Wtd. Avg. Remaining Contractual Life	2 years 3 months 29 days
Options exercisable, Wtd. Avg. exercise price	$ 9.03
14.44 - 22.26 [Member]
Exercise prices and related information of stock option outstanding
Lower range limit, Exercise price	$ 14,440
Upper range limit, Exercise price	$ 22,260.00
Options outstanding, Number outstanding	1,021
Options outstanding, Wtd. Avg. remaining contractual life	6 years 11 months 19 days
Options outstanding, Wtd. Avg. exercise price	$ 19.44
Options exercisable, Number exercisable	629
Options exercisable Wtd. Avg. Remaining Contractual Life	6 years 4 months 13 days
Options exercisable, Wtd. Avg. exercise price	$ 18.59
22.30 - 24.61 [Member]
Exercise prices and related information of stock option outstanding
Lower range limit, Exercise price	$ 22,300
Upper range limit, Exercise price	$ 24,610.00
Options outstanding, Number outstanding	102
Options outstanding, Wtd. Avg. remaining contractual life	9 years 4 months 6 days
Options outstanding, Wtd. Avg. exercise price	$ 22.32
Options exercisable, Number exercisable	18
Options exercisable Wtd. Avg. Remaining Contractual Life	8 years 1 month 6 days
Options exercisable, Wtd. Avg. exercise price	$ 22.36

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

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- Definition

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

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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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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

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-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

-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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-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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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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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.

+ References

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