Treasury and Preferred Stock (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Equity [Abstract] | |||
| Payments for Repurchase of Common Stock | $ 130.0 | $ 120.3 | $ 120.0 |
| Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased | 110,000,000 | ||
| Treasury Stock Activity [Roll Forward] | |||
| Balance at January 1 | 13,221,000 | 11,725,000 | 9,844,000 |
| Compensation Plans and Other | (547,000) | (1,199,000) | (458,000) |
| Share Repurchases | 2,327,000 | 2,695,000 | 2,339,000 |
| Balance at December 31 | 15,001,000 | 13,221,000 | 11,725,000 |
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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 No definition available.
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- References No definition available.
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- Definition The cash outflow to reacquire common stock during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. No definition available.
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- Definition Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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