| **Stock-based Compensation Plans - Schedule of Stock Based Compensation Other than Options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions**   | 12 Months Ended          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value                                                                            |                     | $ 10.53 | $ 14.12 |
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate                                                          | 0.00%                    |   |   |
| Allocated Share-based Compensation Expense                                                                                                                                 | $ 15.0                   | $ 9.0 | $ 16.0 |
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized                                                                          | $ 12.0                   |   |   |
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition                                                  | 1 year 10 months 24 days |   |   |
| Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options                                                                                    |                     | $ 1.0 | $ 19.0 |
| Performance-based Stock Unit [Member]                                                                                                                                      |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 244                      | 292 | 326 |
| Equity Instruments Other than Options, Forfeited in Period                                                                                                                 | (244)                    | (48) | (34) |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 0                        | 244 | 292 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 28.73                  | $ 28.48 | $ 28.35 |
| Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value                                                                                 | 28.73                    | 27.24 | 27.24 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 0.00                   | $ 28.73 | $ 28.48 |
| Market-based Stock Options [Member] [Member]                                                                                                                               |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 615                      | 670 | 759 |
| Equity Instruments Other than Options, Forfeited in Period                                                                                                                 | (48)                     | (55) | (89) |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 567                      | 615 | 670 |
| Equity Instruments Other Than Options, Exercisable, Number                                                                                                                 | 567                      | 0 | 0 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 27.24                  | $ 27.24 | $ 27.24 |
| Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value                                                                                 | 27.24                    | 27.24 | 27.24 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 27.24                  | $ 27.24 | $ 27.24 |
| Share-Settled Restricted Stock Units [Member]                                                                                                                              |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 69                       | 188 | 299 |
| Equity Instruments Other than Options, Grants in Period                                                                                                                    | 624                      | 0 | 0 |
| Equity Instruments Other than Options, Vested in Period                                                                                                                    | (66)                     | (114) | (90) |
| Equity Instruments Other than Options, Forfeited in Period                                                                                                                 | (14)                     | (5) | (21) |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 613                      | 69 | 188 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 28.60                  | $ 28.75 | $ 29.54 |
| Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value                                                                            | 8.76                     | 0.00 | 0.00 |
| Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value                                                                            | 28.66                    | 28.91 | 31.74 |
| Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value                                                                                 | 13.07                    | 27.24 | 27.24 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 8.74                   | $ 28.60 | $ 28.75 |
| Performance-based Stock Options [Member]                                                                                                                                   |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 1,409                    | 941 | 299 |
| Equity Instruments Other than Options, Grants in Period                                                                                                                    | 0                        | 729 | 651 |
| Equity Instruments Other than Options, Forfeited in Period                                                                                                                 | (436)                    | (261) | (9) |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 973                      | 1,409 | 941 |
| Equity Instruments Other Than Options, Exercisable, Number                                                                                                                 | 0                        | 0 | 0 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 31.64                  | $ 35.41 | $ 34.47 |
| Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value                                                                            | 0.00                     | 27.61 | 35.83 |
| Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value                                                                                 | 34.22                    | 33.99 | 35.09 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 30.47                  | $ 31.64 | $ 35.41 |
| Restricted Stock [Member]                                                                                                                                                  |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                                         |                     |   |   |
| Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other than Options, Aggregate Grant Date Fair Value                                  | $ 0.1                    | $ 1.1 | $ 0.1 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 0                        | 41 | 41 |
| Equity Instruments Other than Options, Grants in Period                                                                                                                    | 5                        | 2 | 4 |
| Equity Instruments Other than Options, Vested in Period                                                                                                                    | (5)                      | (43) | (4) |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 0                        | 0 | 41 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 0.00                   | $ 24.13 | $ 24.13 |
| Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value                                                                            | 12.52                    | 29.50 | 33.70 |
| Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value                                                                            | 12.52                    | 24.38 | 33.70 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 0.00                   | $ 0.00 | $ 24.13 |
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period                                                                                    | 3 years                  |   |   |
| Cash-Settled Restricted Stock Units [Member]                                                                                                                               |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 498                      | 469 | 194 |
| Equity Instruments Other than Options, Grants in Period                                                                                                                    | 650                      | 280 | 470 |
| Equity Instruments Other than Options, Vested in Period                                                                                                                    | (231)                    | (190) | (124) |
| Equity Instruments Other than Options, Forfeited in Period                                                                                                                 | (100)                    | (61) | (71) |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 817                      | 498 | 469 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 29.96                  | $ 33.00 | $ 43.74 |
| Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value                                                                            | 7.26                     | 27.67 | 32.44 |
| Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value                                                                            | 26.06                    | 33.82 | 47.48 |
| Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value                                                                                 | 22.19                    | 30.75 | 33.24 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 13.95                  | $ 29.96 | $ 33.00 |
| Employee Service Share-based Compensation, Cash Flow Effect, Cash Used to Settle Awards                                                                                    | $ 2.0                    | $ 6.0 | $ 5.0 |
| Restricted Stock Units (RSUs) [Member]                                                                                                                                     |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                                         |                     |   |   |
| Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other than Options, Aggregate Grant Date Fair Value                                  | $ 8.0                    | $ 10.0 | $ 9.0 |
| Service and Market Measures [Member] | Cash-settled Performance-based Stock Unit [Member]                                                                                  |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 172                      | 172 | 172 |
| Equity Instruments Other than Options, Forfeited in Period                                                                                                                 | (102)                    | 0 | 0 |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 70                       | 172 | 172 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 69.64                  | $ 69.64 | $ 69.64 |
| Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value                                                                                 | 82.86                    | 0.00 | 0.00 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 50.52                  | $ 69.64 | $ 69.64 |
| Service and Performance Measures [Member] | Cash-settled Performance-based Stock Unit [Member]                                                                             |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]**                   |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 434                      | 221 | 0 |
| Equity Instruments Other than Options, Grants in Period                                                                                                                    | 0                        | 277 | 225 |
| Equity Instruments Other than Options, Forfeited in Period                                                                                                                 | (55)                     | (64) | (4) |
| Equity Instruments Other than Options, Nonvested, Number                                                                                                                   | 379                      | 434 | 221 |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 30.64                  | $ 35.11 | $ 0.00 |
| Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value                                                                            | 0.00                     | 27.61 | 35.10 |
| Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value                                                                                 | 30.65                    | 32.95 | 35.09 |
| Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value                                                                                   | $ 30.63                  | $ 30.64 | $ 35.11 |
| Black Scholes [Member] | Performance-based Stock Options [Member]                                                                                                          |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                                         |                     |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate                                                         |                     | 1.40% | 1.60% |
| **Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]** |                     |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate                                                        |                     | 42.90% | 45.50% |
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term                                                                   |                     | 4 years 8 months 12 days | 4 years 10 months 15 days |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other than Options, Aggregate Grant Date Fair Value
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No definition available.
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| - Definition
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Exercisable, Number
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Unrecognized cost of unvested share-based compensation awards.
+ References
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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
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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
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of grants made 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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.
+ References
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| - Definition
The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan 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
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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
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.
+ References
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| - Definition
The risk-free interest rate assumption that is used in valuing an option on its own shares.
+ References
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| - Definition
Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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