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Shareholders' Equity Dividends Declared (Tables) | 6 Months Ended
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Jun. 30, 2019
Shareholders' Equity [Abstract] |
Dividends Declared [Table Text Block] | The following table summarizes year-to-date dividend activity as of June 30, 2019:
Declared |  | Regular Cash Dividends Per Common Share |  | Special Cash Dividends Per Common Share |  | Record Date |  | Paid Date
January 24, 2019 |  | $ | 0.28 |  |  | $ | 0.14 |  |  | February 6, 2019 |  | February 20, 2019
April 25, 2019 |  | $ | 0.28 |  |  | $ | 0.14 |  |  | May 8, 2019 |  | May 22, 2019

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- Definition Shareholders' Equity [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of information related to dividends declared, including paid and unpaid dividends. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
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