Significant Accounting Policies Out of Period Adjustments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Equity Income (Loss)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Immaterial prior period adjustment made in current period	$ 1.7	$ 1.4	$ 0.3

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Balance Type:	na
Period Type:	duration