Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Rental Property (Details)

v3.3.1.900
Summary of Significant Accounting Policies - Rental Property (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Accounting Policies [Abstract]      
Internal development costs, capitalized $ 3.0 $ 1.6 $ 2.2
Interest costs incurred, capitalized $ 3.4 5.1 1.6
Buildings and improvements, estimated useful life 33 years    
Land improvements, estimated useful life 15 years    
Property, plant and equipment, estimated useful life, minimum 7 years    
Real estate depreciation $ 85.9 $ 80.1 $ 74.7
Purchase price allocated to assets, useful life, maximum 33 years