Indebtedness (Tables)

3 Months Ended

Mar. 31, 2014

Debt Disclosure [Abstract]

Fair Value, Liabilities Measured on a Recurring Basis, Disclosure Only

	Book Value at 12/31/13		Book Value at 3/31/14		Fair Value at 12/31/13		Issuances and Assumptions		Payments/Payoffs			Adjustments to Fair Value		Fair Value at 3/31/14
Fixed rate secured debt	$	1,081,035	$	1,058,485	$	1,145,717	$	—	$	(21,365	)	$	11,244	$	1,135,596
Variable rate secured debt	19,089		18,983		19,089		—		(106		)	—		18,983
Unsecured debt	3,066,252		3,065,742		3,250,518		—		(511		)	39,208		3,289,215
Unsecured line of credit	88,000		180,000		88,383		92,000		—			468		180,851
Total	$	4,254,376	$	4,323,210	$	4,503,707	$	92,000	$	(21,982	)	$	50,920	$	4,624,645

Unsecured Line of Credit

Description	Maximum Capacity		Maturity Date	Outstanding Balance at March 31, 2014
Unsecured Line of Credit - Partnership	$	850,000	December 2015	$	180,000