v2.4.0.6

Stock-Based Compensation Stock-Based Compensation Narrative (Details) (USD $) In Millions, except Share data, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012
Stock Incentive Plan [Member] |  |
[Line Items] |  |
Number of shares authorized for issuance under the share based compensation plan | 3,500,000 |
Number of shares available for future grant under the Stock Incentive Plan | 509,259 |
Stock Option or Share Appreciation Right [Member] |  |
[Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fungible Share Provision | 1 |
Awards Other than Stock Options or Share Appreciation Rights [Member] |  |
[Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fungible Share Provision | 1.7 |
Employee Stock Option [Member] |  |
[Line Items] |  |
Award vesting rights | Options generally become exercisable in three equal annual installments beginning one year from the date of grant |
Unrecognized compensation expense | 4.7 |
Unrecognized compensation expense, Expected weighted average period for recognition (years) | 2 years 6 months 20 days |
Stock options expiration period (years) | 10 years |
Restricted Stock Units (RSUs) [Member] |  |
[Line Items] |  |
Unrecognized compensation expense | 30.3 |
Unrecognized compensation expense, Expected weighted average period for recognition (years) | 2 years 1 month 3 days |
Award vesting period | 3 years |
Long Term Performance Restricted Stock Award [Member] |  |
[Line Items] |  |
Restricted Awards Eligible for Vesting |  | 0
Performance Condition Vesting Range, Lower Range Limit | 0.00% |
Performance Condition Vesting Range, Upper Range Limit | 160.00% |
Market Condition Multiplier, Lower Range Limit | 75.00% |
Market Condition Multiplier, Upper Range Limit | 125.00% |
Possible Total Percentage of Shares Vested, Lower Range Limit | 0.00% |
Possible Total Percentage of Shares Vested, Upper Range Limit | 200.00% |
Employee Stock [Member] |  |
[Line Items] |  |
ESPP, percentage discount from market price on purchase date | 15.00% |
ESPP, maximum percentage of employee salary eligible for participation | 10.00% |
Shares available for future issuance under the ESPP | 580,000 |

X
- Definition For awards granted under a stock award plan with a fungible share provision, the number of shares by which the pool of shares reserved and authorized for issuance is reduced as a result of the grant of a particular award type. + References No definition available. + Details
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- Definition For a multiplier payout feature, which provides for the multiplication of shares earned by a percentage factor as the result of achievement against a market condition, the lower range limit of the multiplier, in percentage terms. + References No definition available. + Details
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- Definition For a multiplier payout feature, which provides for the multiplication of shares earned by a percentage factor as the result of achievement against a market condition, the upper range limit of the multiplier, in percentage terms. + References No definition available. + Details
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- Definition For awards with a performance condition that results in a variable percentage of shares being earned, relative to the number of awards originally granted, the lower range limit of the variable percentage range. + References No definition available. + Details
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- Definition For awards with a performance condition that results in a variable percentage of shares being earned, relative to the number of awards originally granted, the upper range limit of the variable percentage range. + References No definition available. + Details
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- Definition For awards whereby a variable percentage of shares will ultimately vest, relative to the number of awards originally granted, based upon the combination of multiple performance or market conditions, the lower range limit of the total variable percentage range. + References No definition available. + Details
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- Definition For awards whereby a variable percentage of shares will ultimately vest, relative to the number of awards originally granted, based upon the combination of multiple performance or market conditions, the upper range limit of the total variable percentage range. + References No definition available. + Details
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- Definition The number of shares of common stock available for future issuance under the employee stock purchase plan as of the balance sheet date. + References No definition available. + Details
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- Definition Stock Options Expiration Period in Years from Grant Date + References No definition available. + Details
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- Definition As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph h -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. + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph a -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. + Details
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- Definition The discount rate from market value on purchase date that participants pay for shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 65 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -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. + Details
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- Definition Other increase (decrease) in number of shares reserved for issuance under non-option equity instrument agreements that is not separately disclosed. + References No definition available. + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph a -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 (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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