Organization and Principles of Consolidation Recent accounting pronouncements (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Document Period End Date	Mar. 31, 2015
Parent Company [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Proceeds from Issuance of Debt	9.7

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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