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| Quarterly Financial Information [Table Text Block] |
| us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock |
| Tabular disclosure of quarterly financial data. Includes, but is not limited to, financial information for fiscal quarters, cumulative effect of a change in accounting principle and earnings per share data. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:ScheduleOfQuarterlyFinancialInformationTableTextBlock |
| QuarterlyFinancialInformationDuplicate |