Activity in the Allowance for Credit Losses (Details) - Commercial Real Estate Portfolio Segment - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Financing Receivable, Allowance for Credit Losses
Allowance Balance at Beginning of Year	$ 1.5	$ 4.5	$ 1.5	$ 1.5
Provision for Loan Losses	0.5	0.0	0.5	3.0
Allowance Balance at End of Period	$ 2.0	$ 4.5	$ 2.0	$ 4.5