Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]

Deferred leasing costs and acquired lease-related intangible assets at December 31, 2017 and 2016, excluding amounts classified as held-for-sale, were as follows (in thousands):



	2017			2016
Deferred leasing costs	$	312,206		$	275,491
Acquired lease-related intangible assets	189,927			170,048
	$	502,133		$	445,539

Accumulated amortization - deferred leasing costs	$	(108,177	)	$	(95,343	)
Accumulated amortization - acquired lease-related intangible assets	(101,274		)	(91,455		)
Total	$	292,682		$	258,741

Schedule of Future Amortized Expense and Charge to Rental Income

The expected future amortization, or charge to rental income, of acquired lease-related intangible assets is summarized in the table below (in thousands):



Year	Amortization Expense		Charge to Rental Income
2018	$	21,904	$	777
2019	16,455		703
2020	12,700		639
2021	9,563		367
2022	7,080		353
Thereafter	17,701		411
	$	85,403	$	3,250

Schedule of Earnings Per Share, Basic and Diluted

The following table reconciles the components of basic and diluted net income per common share or Common Unit (in thousands):



	2017			2016			2015
General Partner
Net income attributable to common shareholders	$	1,634,431		$	312,143		$	615,310
Less: Dividends on participating securities	(3,981		)	(2,356		)	(3,081		)
Basic net income attributable to common shareholders	1,630,450			309,787			612,229
Add back dividends on dilutive participating securities	3,981			2,356			3,081
Noncontrolling interest in earnings of common unitholders	15,176			3,089			6,404
Diluted net income attributable to common shareholders	$	1,649,607		$	315,232		$	621,714
Weighted average number of common shares outstanding	355,762			349,942			345,057
Weighted average Limited Partner Units outstanding	3,303			3,481			3,582
Other potential dilutive shares	2,946			3,653			3,558
Weighted average number of common shares and potential dilutive securities	362,011			357,076			352,197

Partnership
Net income attributable to common unitholders	$	1,649,607		$	315,232		$	621,714
Less: Distributions on participating securities	(3,981		)	(2,356		)	(3,081		)
Basic net income attributable to common unitholders	$	1,645,626		$	312,876		$	618,633
Add back distributions on dilutive participating securities	3,981			2,356			3,081
Diluted net income attributable to common unitholders	$	1,649,607		$	315,232		$	621,714
Weighted average number of Common Units outstanding	359,065			353,423			348,639
Other potential dilutive units	2,946			3,653			3,558
Weighted average number of Common Units and potential dilutive securities	362,011			357,076			352,197

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

The following table summarizes the data that is excluded from the computation of net income per common share or Common Unit as a result of being anti-dilutive (in thousands):



	2017	2016	2015
General Partner and Partnership
Other potential dilutive shares or units:
Anti-dilutive outstanding potential shares or units under fixed stock option and other stock-based compensation plans	—	175	997
Anti-dilutive outstanding participating securities	—	—	—

Reconciliation of Net Income to Taxable Income Before Dividends Paid Deduction

The following table reconciles the General Partner's net income to taxable income before the dividends paid deduction, and subject to the 90% distribution requirement, for the years ended December 31, 2017, 2016 and 2015 (in thousands):



	2017			2016			2015
Net income	$	1,654,341		$	315,278		$	621,861
Book/tax differences	(1,076,060		)	(61,133		)	(316,097		)
Taxable income before the dividends paid deduction	578,281			254,145			305,764
Less: capital gains	(441,836		)	(63,550		)	(294,901		)
Adjusted taxable income subject to the 90% distribution requirement	$	136,445		$	190,595		$	10,863

Computation of Dividends Paid Deduction

The General Partner's dividends paid deduction is summarized below (in thousands):



	2017			2016			2015
Cash dividends paid	$	576,832		$	255,279		$	307,169
Cash dividends declared and paid in subsequent year that apply to current year	2,500			—			—
Less: Return of capital	—			(6,717		)	—
Plus: Deemed REIT distribution	—			6,717			—
Dividends paid deduction	579,332			255,279			307,169
Less: Capital gain distributions	(441,836		)	(63,550		)	(294,901		)
Dividends paid deduction attributable to adjusted taxable income subject to the 90% distribution requirement	$	137,496		$	191,729		$	12,268

Summary of Tax Characterization of Dividends Paid

A summary of the tax characterization of the dividends paid by the General Partner for the years ended December 31, 2017, 2016 and 2015 is as follows:



	2017		2016		2015
Common Shares
Ordinary income	23.7	%	72.6	%	4.2	%
Return of capital	—	%	2.6	%	—	%
Capital gains	76.3	%	24.8	%	95.8	%
	100.0	%	100.0	%	100.0	%

Fair Value Measurements, Nonrecurring [Table Text Block]

The table below aggregates the total fair value of these impaired assets as determined during the years ended December 31, 2017, 2016 and 2015, respectively, by the levels in the fair value hierarchy (in thousands):



	2017				2016				2015
	Level 1	Level 2	Level 3		Level 1	Level 2	Level 3		Level 1	Level 2	Level 3
Real estate assets	—	—	$	14,299	—	—	$	34,744	—	—	$	31,100
Investment in land joint ventures	—	—	—		—	—	—		—	—	$	19,500