Derivative and Hedging Activities (Effect of Derivative Instruments on the Consolidated Statement of Operations and Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Effect of derivative instruments on the Consolidated Statement of Operations and Comprehensive Income [Abstract]
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 15,000		$ 15,000
Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	1,094	$ (9,956)	(16,057)	$ (16,267)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(3,286)	423	(4,054)	1,846
Consolidated Properties [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member] \| Other comprehensive income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	922	(8,808)	(14,623)	(14,524)
Consolidated Properties [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member] \| Interest expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(2,869)	(72)	(4,080)	766
Unconsolidated Properties [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member] \| Other comprehensive income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	124	(1,075)	(1,440)	(1,700)
Unconsolidated Properties [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member] \| Equity Method Investments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(263)	132	(294)	269
Unconsolidated Properties [Member] \| Cash Flow Hedging [Member] \| Cross Currency Interest Rate Contract [Member] \| Other comprehensive income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	48	(73)	6	(43)
Unconsolidated Properties [Member] \| Cash Flow Hedging [Member] \| Cross Currency Interest Rate Contract [Member] \| Equity Method Investments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (154)	$ 363	$ 320	$ 811

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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