Basis of Presentation and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Basis of Presentation and Significant Accounting Policies [Abstract]

Reconciliation Of Net Income Attributable To Common Shareholders To Estimated Taxable Income [Table Text Block]

(Amounts in thousands)			For the Year Ended December 31,
			2015		2014		2013
Net income attributable to common shareholders		$	679,856	$	783,388	$	392,034
Book to tax differences (unaudited):
	Tangible Property Regulations (1)		(575,618)		-		-
	Sale of real estate and other capital transactions		320,326		(477,061)		(324,936)
	Depreciation and amortization		227,297		219,403		155,401
	Straight-line rent adjustments		(144,727)		(77,526)		(64,811)
	Stock options		(8,278)		(9,566)		4,884
	Earnings of partially owned entities		(5,299)		71,960		339,376
	Impairment losses on marketable equity securities		-		-		37,236
	Other, net		(5,833)		1,260		36,186
Estimated taxable income (unaudited)		$	487,724	$	511,858	$	575,370
(1)	Represents one-time deductions pursuant to the implementation of the Tangible Property Regulations issued by the Internal Revenue Service.