Lease Intangibles, net - Narrative (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2014
Sep. 30, 2013
Capital Leased Assets [Line Items]        
Amortization amount to rental revenue for capitalized leases $ 1.6 $ 0.7 $ 4.6 $ 1.4
In-place Leases
       
Capital Leased Assets [Line Items]        
Leases amortization expenses $ 13.1 $ 10.9 $ 40.0 $ 19.8