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Impairment Charges and Impairment of Joint Venture Investments - Summary of Significant Unobservable Inputs (Detail) - Fair Value Measurements [Member]
$ in Millions
12 Months Ended
Dec. 31, 2016
USD ($)
$ / ft²
Dec. 31, 2015
USD ($)
$ / ft²
Dec. 31, 2014
USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Fair Value $ 438.2 $ 407.1 $ 141.2
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Income Capitalization/Sales Comparison Approach [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Fair Value $ 398.2 $ 287.6  
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Income Capitalization/Sales Comparison Approach [Member] | Minimum [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Range 7.00% 8.00%  
Price per Square Foot, Range | $ / ft² 15.00 10.00  
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Income Capitalization/Sales Comparison Approach [Member] | Maximum [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Range 10.00% 9.00%  
Price per Square Foot, Range | $ / ft² 31.00 40.00  
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Discounted Cash Flow [Member] | Minimum [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Range 10.00% 10.00%  
Range 10.00% 8.00%  
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Discounted Cash Flow [Member] | Maximum [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Range 11.00% 14.00%  
Range 12.00% 10.00%  
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Indicative Bid/Contracted Price [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Fair Value $ 13.4 $ 33.8  
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Indicative Bid [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Fair Value 26.6 51.5  
Impairment of Consolidated Assets [Member] | Level 3 [Member] | Indicative Bid/Sales Comparison Approach [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Fair Value $ 0.0 $ 34.2