| **Earnings per Common Share - Textual (Details) $ / shares in Units, shares in Millions, $ in Millions** |        |                                            |         | 1 Months Ended | 3 Months Ended |        |
|----------------------------------------------------------------------------------------------------------|--------|--------------------------------------------|---------|----------------|----------------|--------|
||
| **Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]**                |   |                                       |    |           |           |   |   |   |   |   |
| Cash dividends per common share, Declared (in dollars per share)                                         | $ 0.24 |                                       |    |           |           |   |   | $ 0.24 | $ 0.23 |   |
| Stock Issued During Period, Value, Warrants Exercised, Shares | shares                                   |   |                                       | 5.0     |           |           |   | 0.7 |   |   |   |
| Class of Warrant or Right, Outstanding | shares                                                          |   |                                       | 8.2     |           |           |   | 0.0 |   |   | 8.2 |
| Exercise price of warrants (in dollars per share)                                                        |   |                                       | $ 41.40 |           |           |   | $ 41.40 |   |   | $ 41.40 |
| Proceeds from exercising stock warrants | $                                                              |   |                                       |    |           |           |   | $ 27.0 | $ 26.6 | $ 0.0 |   |
| Senior Subordinated Notes [Member] | 2.00% Convertible Senior Subordinated Notes due 2043 [Member]       |   |                                       |    |           |           |   |   |   |   |   |
| **Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]**                |   |                                       |    |           |           |   |   |   |   |   |
| Convertible debt conversion price (in dollars per share)                                                 |   | $ 39.65                                    |    |           |           |   |   | $ 36.74 |   |   |
| Convertible debt conversion terms                                                                        |   | 25.2194 shares per $1,000 principal amount |    |           |           |   |   |   |   |   |
| Convertible debt conversion ratio (in shares per $1000)                                                  |   | 25.2194                                    |    |           |           |   |   | 27.2221 |   |   |
| Common Stock                                                                                             |   |                                       |    |           |           |   |   |   |   |   |
| **Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]**                |   |                                       |    |           |           |   |   |   |   |   |
| Cash dividends per common share, Declared (in dollars per share)                                         |   |                                       |    |           | $ 0.24         |   |   |   |   |   |
| Cash dividends per common share, Paid (in dollars per share)                                             |   |                                       |    |           |           | $ 0.24 |   |   |   |   |
| Common stock dividends accrued | $                                                                       |   |                                       |    |           |           |   |   | $ 22.0 |   | $ 22.2 |
| Subsequent Event [Member] | Common Stock                                                                 |   |                                       |    |           |           |   |   |   |   |   |
| **Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]**                |   |                                       |    |           |           |   |   |   |   |   |
| Cash dividends per common share, Paid (in dollars per share)                                             |   |                                       |    | $ 0.24         |           |   |   |   |   |   |

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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The stock warrants exercises resulted in the issuance of shares of common stock.
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| - Definition
Exercise price per share or per unit of warrants or rights outstanding.
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| - Definition
Number of warrants or rights outstanding.
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| - Definition
Aggregate dividends paid during the period for each share of common stock outstanding.
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| - Definition
Aggregate dividends declared during the period for each share of common stock outstanding.
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| - Definition
The price per share of the conversion feature embedded in the debt instrument.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.
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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.
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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).
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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.
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| - Definition
The cash inflow associated with the amount received from holders exercising their stock warrants.
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