Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Long-term Debt
Transfers between Levels 1 and 2, description	The Company did not have transfers between Levels 1 and 2 for either financial assets or liabilities, during the three months ended March 31, 2016 or 2015.
Fair Value [Member] | Senior Unsecured Notes [Member]
Long-term Debt
Debt	$ 295.5	$ 305.6
Carrying Value [Member] | Senior Unsecured Notes [Member]
Long-term Debt
Debt	$ 299.1	$ 299.0