Goodwill and Other Intangibles (Projected Amortization Expense and Adjustments) (Details) $ in Thousands	Mar. 31, 2016 USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Below-market lease liabilities, amortization income, April 1, 2016 - December 31, 2016	$ 23,115
Below-market lease liabilities, amortization income, 2017	20,453
Below-market lease liabilities, amortization income, 2018	20,126
Below-market lease liabilities, amortization income, 2019	19,388
Below-market lease liabilities, amortization income, 2020	18,196
In-Place Leases [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization expense, April 1, 2016 - December 31, 2016	168,216
Amortization expense, 2017	154,275
Amortization expense, 2018	141,317
Amortization expense, 2019	129,711
Amortization expense, 2020	120,676
Leasing Commissions [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization expense, April 1, 2016 - December 31, 2016	1,341
Amortization expense, 2017	682
Amortization expense, 2018	496
Amortization expense, 2019	425
Amortization expense, 2020	407
Above-Market Lease Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization expense, April 1, 2016 - December 31, 2016	25,672
Amortization expense, 2017	25,309
Amortization expense, 2018	24,756
Amortization expense, 2019	22,801
Amortization expense, 2020	$ 22,334