Identified Intangible Assets and Intangible Liabilities (Tables)

3 Months Ended

Mar. 31, 2014

Finite-Lived Intangible Assets [Line Items]

Schedule of Identified Intangible Assets and Intangible Liabilities [Table Text Block]

	Balance as of
	March 31,		December 31,
(Amounts in thousands)	2014		2013
Identified intangible assets:
Gross amount	$	589,973	$	589,961
Accumulated amortization		(290,214)		(277,998)
Net	$	299,759	$	311,963
Identified intangible liabilities (included in deferred revenue):
Gross amount	$	850,765	$	856,933
Accumulated amortization		(367,972)		(360,398)
Net	$	482,793	$	496,535

Below Market Leases Net Of Above Market Leases [Member]

Finite-Lived Intangible Assets [Line Items]

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

(Amounts in thousands)
2015	$	39,972
2016		38,631
2017		34,929
2018		33,309
2019		30,072

Other Identified Intangible Assets [Member]

Finite-Lived Intangible Assets [Line Items]

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

(Amounts in thousands)
2015	$	23,254
2016		20,237
2017		16,821
2018		12,441
2019		11,535

Tenant Under Ground Leases [Member]

Finite-Lived Intangible Assets [Line Items]

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

(Amounts in thousands)
2015	$	3,430
2016		3,430
2017		3,430
2018		3,430
2019		3,430