Variable Interest Entities (Details) (Variable Interest Entity, Primary Beneficiary [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Variable Interest Entity [Line Items]
Noncontrolling Interest in Variable Interest Entity	$ 58.8	$ 58.4
Variable Interest Entity, Consolidated, Carrying Amount, Assets	141.3	139.9
New Ocean Capital Management Ltd [Member]
Variable Interest Entity [Line Items]
Noncontrolling Interest in Variable Interest Entity	$ 0.2	$ 0.2