Common Stock (Narrative) (Details) - $ / shares |
Dec. 31, 2017 |
Dec. 23, 2009 |
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| Common Stock [Abstract] | ||
| Remaining number of shares authorized to be repurchased | 411,910 | |
| Number of rights distributed for each share of common stock | 1 | |
| Number of securities into which each right may be converted | 0.01 | |
| Exercise price of right | $ 41 | |
| Percentage of common stock required to be purchased for rights to become exercisable | 16.50% |
| X | ||||||||||
- Definition Class of Warrant or Right, Number of Rights Distributed by Securities No definition available.
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- Definition Percentage of common stock required to be purchased for rights to become exercisable No definition available.
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- Definition Exercise price per share or per unit of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares. No definition available.
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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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- References No definition available.
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