Long-term Debt (Schedule of Mortgage Notes Payable) (Details) (Details) (Mortgages [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Aggregate Principal Outstanding	$ 241.5	$ 118.9
Carrying Value of Collateralized Related Real Estate	361.4	152.4
Real Estate Credit Agreement [Member]
Debt Instrument [Line Items]
Aggregate Principal Outstanding	75.0	0
Carrying Value of Collateralized Related Real Estate	131.0	0
Master Loan Agreement [Member]
Debt Instrument [Line Items]
Aggregate Principal Outstanding	18.4	19.7
Carrying Value of Collateralized Related Real Estate	34.3	35.5
Captive Mortgage [Member]
Debt Instrument [Line Items]
Aggregate Principal Outstanding	122.7	73.2
Carrying Value of Collateralized Related Real Estate	157.5	81.4
Other Mortgage Debt [Member]
Debt Instrument [Line Items]
Aggregate Principal Outstanding	25.4	26.0
Carrying Value of Collateralized Related Real Estate	$ 38.6	$ 35.5