Noncontrolling Interests (Noncontrolling Interests-Redeemable Common Units) (Details) (Noncontrolling Interests [Member], USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Noncontrolling Interests [Member]
Activity of noncontrolling interests
Beginning Balance	$ 1,836,522	$ 1,809,119
Contributions	26,384	24,653
Net income	74,395	27,386
Distributions	(33,956)	(30,100)
Conversion of redeemable partnership units	(10,406)	(11,236)
Unearned compensation	(2,262)	(4,832)
Accumulated other comprehensive loss	189	208
Adjustments to reflect redeemable partnership units at redemption value	(52,323)	187,038
Ending Balance	$ 1,838,543	$ 2,002,236

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References+ Details