Goodwill and Other Intangible Assets - Goodwill (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Investment Management
Goodwill [Line Items]
Goodwill	31.1	31.1
Management contract rights
Goodwill [Line Items]
Weighted Average Amortization Lives	20 years	20 years
Customer relationship lists
Goodwill [Line Items]
Weighted Average Amortization Lives	20 years	20 years
Computer software
Goodwill [Line Items]
Weighted Average Amortization Lives	3 years	3 years