Share Based Compensation Plans (Details 2) (Stock Options [Member], USD $)	12 Months Ended
Dec. 31, 2012
Summary of information about options outstanding
Number Outstanding	1,001,241
Number Exercisable and Fully Vested	172,122
$ 0 - $ 5 [Member]
Summary of information about options outstanding
Range of Exercise Price, Lower Range Limit	$ 0
Range of Exercise Price, Upper Range Limit	$ 5
Number Outstanding	561,811
Weighted Average Remaining Life in Years	7 years 4 days
Weighted Average Exercise Price	$ 0.59
Number Exercisable and Fully Vested	128,617
Weighted Average Remaining Life in Years	6 years 15 days
Weighted Average Exercise Price	$ 0.69
$ 5 - $10 [Member]
Summary of information about options outstanding
Range of Exercise Price, Lower Range Limit	$ 5
Range of Exercise Price, Upper Range Limit	$ 10
Number Outstanding	20,654
Weighted Average Remaining Life in Years	2 years 8 months 16 days
Weighted Average Exercise Price	$ 9.93
Number Exercisable and Fully Vested	20,654
Weighted Average Remaining Life in Years	2 years 8 months 16 days
Weighted Average Exercise Price	$ 9.93
$10 - $15 [Member]
Summary of information about options outstanding
Range of Exercise Price, Lower Range Limit	$ 10
Range of Exercise Price, Upper Range Limit	$ 15
Number Outstanding	355,233
Weighted Average Remaining Life in Years	2 years 2 months 1 day
Weighted Average Exercise Price	$ 11.27
Number Exercisable and Fully Vested	0
Weighted Average Remaining Life in Years	0 years
Weighted Average Exercise Price	$ 0.00
$20 - $25 [Member]
Summary of information about options outstanding
Range of Exercise Price, Lower Range Limit	$ 20
Range of Exercise Price, Upper Range Limit	$ 25
Number Outstanding	11,185
Weighted Average Remaining Life in Years	5 years 2 months 5 days
Weighted Average Exercise Price	$ 20.57
Number Exercisable and Fully Vested	11,185
Weighted Average Remaining Life in Years	5 years 2 months 5 days
Weighted Average Exercise Price	$ 20.57
$25 - $30 [Member]
Summary of information about options outstanding
Range of Exercise Price, Lower Range Limit	$ 25
Range of Exercise Price, Upper Range Limit	$ 30
Number Outstanding	50,978
Weighted Average Remaining Life in Years	7 years 10 months 2 days
Weighted Average Exercise Price	$ 28.59
Number Exercisable and Fully Vested	11,666
Weighted Average Remaining Life in Years	4 years 1 month 21 days
Weighted Average Exercise Price	$ 27.09
$30 - $35 [Member]
Summary of information about options outstanding
Range of Exercise Price, Lower Range Limit	$ 30
Range of Exercise Price, Upper Range Limit	$ 35
Number Outstanding	1,380
Weighted Average Remaining Life in Years	8 years 4 months 13 days
Weighted Average Exercise Price	$ 32.60
Number Exercisable and Fully Vested	0
Weighted Average Remaining Life in Years	0 years
Weighted Average Exercise Price	$ 0.00

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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.

+ References

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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

-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 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

-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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-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.

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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

+ Details

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