Defined contribution plan contributions by employer

No definition available.

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- Definition

Defined contribution plan contributions from employees annual compensation percentage.

+ References

No definition available.

+ Details

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- Definition

For each of common stock share, reduction of the reserved shares for issuance.

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award, options, vested in period, fair value

+ References

No definition available.

+ Details

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- Definition

Share based compensation options vesting period one year after the grant date percentage

+ References

No definition available.

+ Details

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- Definition

Share based compensation options vesting period semi annually percentage

+ References

No definition available.

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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

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

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- Definition

The date when the equity-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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- Definition

Description of the period of time over 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, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ 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(2)(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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-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 Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

+ Details

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

+ 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

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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

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

+ Details

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- Definition

The number of shares newly issued during the reporting period under the plan.

+ References

Reference 1: 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 2: 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.

Reference 3: 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

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Stock-Based Compensation And Employee Benefit Plans (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended			12 Months Ended
	Dec. 31, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 2008 Stock Incentive Plan [Member]	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2009 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2011 Non-Qualified [Member]	Dec. 31, 2011 Restricted Stock Awards [Member] years	Dec. 31, 2010 Restricted Stock Awards [Member]	Dec. 31, 2009 Restricted Stock Awards [Member]	Dec. 31, 2011 Restricted Stock Awards [Member] 2008 Stock Incentive Plan [Member]	Dec. 31, 2011 Employee Stock Option [Member] years	Dec. 31, 2010 Employee Stock Option [Member]	Dec. 31, 2009 Employee Stock Option [Member]	Dec. 31, 2011 Employee Stock Option [Member] 2008 Stock Incentive Plan [Member]	Dec. 31, 2011 Maximum [Member]	Dec. 31, 2011 Maximum [Member] Restricted Stock Awards [Member]	Dec. 31, 2011 Maximum [Member] MFR Option Awards [Member]	Dec. 31, 2011 Minimum [Member]	Dec. 31, 2011 Minimum [Member] Restricted Stock Awards [Member]	Dec. 31, 2011 Minimum [Member] MFR Option Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for issuance	38,500,000	38,500,000		20,300,000
For each of common stock share, reduction of the reserved shares for issuance											1.94				1
Stock options issued	137,000
Number of shares available for grant				4,500,000
Weighted-average grant date fair value of options granted												$ 7.09	$ 7.11	$ 6.54
Total intrinsic value of options exercised												$ 12.6	$ 37.6	$ 14.5
Total fair value of options vested												16.1	8.9	8.8
Total fair value of RSU awards vested								6.9	8.4	4.2
Unrecognized stock-based compensation cost								2.9				52.3
Weighted-average recognized period (years)								0.9				4.1
Vesting period					3 years		5 years										6 years	6 years		3 years	3 years
Weighted-average grant-date fair value						$ 12.49
Expected dividend yield												0.00%	0.00%	0.00%
Contributions from employees annual compensation, percentage																100.00%			1.00%
Discretionary matching contributions		$ 3.4	$ 2.9
Expire term							10
Stock options vesting period one year after the grant date percentage		20.00%
Stock options vesting period semiannual percentage		10.00%