Subsequent Events (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Subsequent Event [Line Items]
Other Underwriting Expense	$ 56.5	$ 51.3	$ 165.5	$ 152.6
UNITED STATES | Sale of Sirius [Member]
Subsequent Event [Line Items]
Stop Loss Limitation			45.0
Industry Loss Trigger on Industry Loss Warranty			15,000.0
UNITED STATES | Combination One | Sale of Sirius [Member]
Subsequent Event [Line Items]
Stop Loss Limitation			75.0
Industry Loss Trigger on Industry Loss Warranty			40,000.0
UNITED STATES | Combination Two | Sale of Sirius [Member]
Subsequent Event [Line Items]
Stop Loss Limitation			22.5
Industry Loss Trigger on Industry Loss Warranty			50,000.0
JAPAN | Sale of Sirius [Member]
Subsequent Event [Line Items]
Stop Loss Limitation			25.0
Industry Loss Trigger on Industry Loss Warranty			$ 12,500.0