Lease Intangibles, Net - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Capital Leased Assets [Line Items]    
Amortization amount to rental revenue for capitalized leases $ 1.5 $ 1.0
Amortization amount to rental revenue for capitalized leases due to merger 0.5  
In-place Leases
   
Capital Leased Assets [Line Items]    
Leases amortization expenses 19.8 13.4
Lease amortization expense due to merger $ 6.5