Identified Intangible Assets and Intangible Liabilities (Tables)

12 Months Ended

Dec. 31, 2014

Finite-Lived Intangible Assets [Line Items]

Schedule of Identified Intangible Assets and Intangible Liabilities (Table)

	Balance as of December 31,
(Amounts in thousands)	2014		2013
Identified intangible assets:
Gross amount	$	502,080	$	583,862
Accumulated amortization		(225,841)		(276,426)
Net	$	276,239	$	307,436
Identified intangible liabilities (included in deferred revenue):
Gross amount	$	885,763	$	855,860
Accumulated amortization		(396,895)		(359,371)
Net	$	488,868	$	496,489

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	$	57,202
2016		45,333
2017		42,457
2018		41,311
2019		30,950

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	$	27,210
2016		21,437
2017		17,859
2018		13,533
2019		11,553

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	$	3,363
2016		3,363
2017		3,363
2018		3,363
2019		3,363