Stock-Based Compensation (Details 2) (Stock Options, USD $)	12 Months Ended
Dec. 31, 2012
Information of stock options by exercise price range.
Number Outstanding (in shares)	5,106,629
Outstanding Weighted-Average Exercise Price (in dollars per share)	$ 14.32
Outstanding Weighted-Average Remaining Life	5 years 6 months 4 days
Number Exercisable (in shares)	2,850,335
Exercisable Weighted-Average Exercise Price (in dollars per share)	$ 18.06
$ 0.00 - 6.99
Information of stock options by exercise price range.
Range of Exercise Prices, minimum (in dollars per share)	$ 0.00
Range of Exercise Prices, maximum (in dollars per share)	$ 6.99
Number Outstanding (in shares)	1,008,750
Outstanding Weighted-Average Exercise Price (in dollars per share)	$ 6.04
Outstanding Weighted-Average Remaining Life	5 years 10 months 24 days
Number Exercisable (in shares)	535,250
Exercisable Weighted-Average Exercise Price (in dollars per share)	$ 6.04
$ 7.00 - 10.99
Information of stock options by exercise price range.
Range of Exercise Prices, minimum (in dollars per share)	$ 7.00
Range of Exercise Prices, maximum (in dollars per share)	$ 10.99
Number Outstanding (in shares)	933,000
Outstanding Weighted-Average Exercise Price (in dollars per share)	$ 8.81
Outstanding Weighted-Average Remaining Life	9 years 3 months 18 days
Number Exercisable (in shares)	15,000
Exercisable Weighted-Average Exercise Price (in dollars per share)	$ 7.86
$ 11.00 - 11.99
Information of stock options by exercise price range.
Range of Exercise Prices, minimum (in dollars per share)	$ 11.00
Range of Exercise Prices, maximum (in dollars per share)	$ 11.99
Number Outstanding (in shares)	860,625
Outstanding Weighted-Average Exercise Price (in dollars per share)	$ 11.90
Outstanding Weighted-Average Remaining Life	6 years 10 months 24 days
Number Exercisable (in shares)	291,125
Exercisable Weighted-Average Exercise Price (in dollars per share)	$ 11.90
$ 12.00 - 15.99
Information of stock options by exercise price range.
Range of Exercise Prices, minimum (in dollars per share)	$ 12.00
Range of Exercise Prices, maximum (in dollars per share)	$ 15.99
Number Outstanding (in shares)	684,626
Outstanding Weighted-Average Exercise Price (in dollars per share)	$ 14.36
Outstanding Weighted-Average Remaining Life	6 years 11 days
Number Exercisable (in shares)	389,332
Exercisable Weighted-Average Exercise Price (in dollars per share)	$ 15.16
$ 16.00 - 24.49
Information of stock options by exercise price range.
Range of Exercise Prices, minimum (in dollars per share)	$ 16.00
Range of Exercise Prices, maximum (in dollars per share)	$ 24.49
Number Outstanding (in shares)	657,216
Outstanding Weighted-Average Exercise Price (in dollars per share)	$ 21.10
Outstanding Weighted-Average Remaining Life	1 year 4 months 6 days
Number Exercisable (in shares)	657,216
Exercisable Weighted-Average Exercise Price (in dollars per share)	$ 21.10
$ 24.50 - 28.85
Information of stock options by exercise price range.
Range of Exercise Prices, minimum (in dollars per share)	$ 24.50
Range of Exercise Prices, maximum (in dollars per share)	$ 28.85
Number Outstanding (in shares)	962,412
Outstanding Weighted-Average Exercise Price (in dollars per share)	$ 25.87
Outstanding Weighted-Average Remaining Life	2 years 7 months 20 days
Number Exercisable (in shares)	962,412
Exercisable Weighted-Average Exercise Price (in dollars per share)	$ 25.87

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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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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)

-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

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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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a, b)

-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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- 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

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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

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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

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