| **Earnings per Common Share - Textual (Details) - USD ($) $ / shares in Units, $ in Millions** |        | 1 Months Ended | 3 Months Ended |        |                                            |
|------------------------------------------------------------------------------------------------|--------|----------------|----------------|--------|--------------------------------------------|
||
| **Earnings per Common Share (Textual) [Abstract]**                                             |   |           |           |   |                                       |   |   |   |
| Cash dividends per common share, Declared                                                      |   |           |           |   | $ 0.23                                     | $ 0.21 |   |   |
| Common Stock                                                                                   |   |           |           |   |                                       |   |   |   |
| **Earnings per Common Share (Textual) [Abstract]**                                             |   |           |           |   |                                       |   |   |   |
| Cash dividends per common share, Declared                                                      | $ 0.23 |           | $ 0.23         |   |                                       |   |   |   |
| Cash dividends per common share, Paid                                                          |   |           |           | $ 0.23 |                                       |   |   |   |
| Dividends Payable, Current                                                                     |   |           |           |   | $ 21.2                                     |   |   | $ 21.3 |
| 2.00% Convertible Senior Subordinated Notes due 2043 [Member]                                  |   |           |           |   |                                       |   |   |   |
| **Earnings per Common Share (Textual) [Abstract]**                                             |   |           |           |   |                                       |   |   |   |
| Debt Instrument, Convertible, Conversion Price                                                 |   |           |           |   | $ 39.65                                    |   |   |   |
| Debt Instrument, Convertible, Terms of Conversion Feature                                      |   |           |           |   | 25.2194 shares per $1,000 principal amount |   |   |   |
| Subsequent Event [Member] | Common Stock                                                       |   |           |           |   |                                       |   |   |   |
| **Earnings per Common Share (Textual) [Abstract]**                                             |   |           |           |   |                                       |   |   |   |
| Cash dividends per common share, Paid                                                          |   | $ 0.23         |           |   |                                       |   |   |   |
| Subsequent Event [Member] | 2.00% Convertible Senior Subordinated Notes due 2043 [Member]      |   |           |           |   |                                       |   |   |   |
| **Earnings per Common Share (Textual) [Abstract]**                                             |   |           |           |   |                                       |   |   |   |
| Debt Instrument, Convertible, Conversion Price                                                 |   |           |           |   |                                       |   | $ 37.59 |   |
| Debt Instrument, Convertible, Shares Issued Upon Conversion                                    |   |           |           |   |                                       |   | 26.6011 |   |

| X                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares issued for each convertible note that is converted.
+ References
No definition available.
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| X                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Earnings Per Common Share.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate dividends paid during the period for each share of common stock outstanding.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate dividends declared during the period for each share of common stock outstanding.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The price per share of the conversion feature embedded in the debt instrument.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).
+ References
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| X                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------|
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