Investments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Investment [Line Items]
Overall default probabilities percentage	0.52%
Recovery and prepayment probabilities percentage	2.00%
Discount rate assumption	11.80%
Non-credit related OTTI recognized in other comprehensive income ("OCI")	$ 0.2
Investments available-for-sale book value	200.2	186.6
Investments held-to-maturity book value	206.6	165.8
Banks and Financial Institutions [Member]
Investment [Line Items]
Trust preferred portfolio fair value	1.2
Trust preferred portfolio	1.3
Government National Mortgage Association Certificates and Obligations (GNMA) [Member] | Federal Home Loan Mortgage and Federal National Mortgage Association [Member]
Investment [Line Items]
Mortgage-backed portfolio	176.2
Government National Mortgage Association Certificates and Obligations (GNMA) [Member] | Federal Home Loan Mortgage and Federal National Mortgage Association [Member] | Federal Home Loan Mortgage Corporation [Member]
Investment [Line Items]
Mortgage-backed portfolio	$ 203.7