Derivative Instruments (Summary of the Effect of Derivative Instruments on the Consolidated Statements of Changes in Equity and Income) (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended		3 Months Ended					6 Months Ended				3 Months Ended				6 Months Ended				3 Months Ended			6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Mar. 31, 2011 Interest Expense [Member] Interest Rate Swap [Member]	Mar. 31, 2011 Costs Associated with Loan Refinancing [Member] Interest Rate Swap [Member]	Mar. 31, 2011 Cross Currency Swaps [Member] Gain on Sale of Real Estate [Member]	Jun. 30, 2010 Interest Rate Swap [Member]		Jun. 30, 2011 Interest Rate Swap [Member]		Jun. 30, 2010 Interest Rate Swap [Member]		Jun. 30, 2011 Cross Currency Swaps [Member]		Jun. 30, 2010 Cross Currency Swaps [Member]		Jun. 30, 2011 Cross Currency Swaps [Member]		Jun. 30, 2010 Cross Currency Swaps [Member]		Jun. 30, 2011 Currency Forward Agreements [Member]		Jun. 30, 2010 Currency Forward Agreements [Member]	Jun. 30, 2011 Currency Forward Agreements [Member]		Jun. 30, 2010 Currency Forward Agreements [Member]
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)	$ (1,202)	$ (6,323)	$ (13,381)	$ (11,858)				$ (12,905)		$ (4,125)		$ (16,022)		$ (339)		$ 2,173		$ (1,479)		$ 1,004		$ (863)		$ 4,409	$ (7,777)		$ 3,160
Amount of Income (Expense) Reclassified from AOCI into Earnings (Effective Portion)	$ (338)	$ (10,445)	$ (9,535)	$ (12,258)	$ 137,000	$ 4,600	$ 4,300	$ (10,424)	[1]	$ (4,722)	[1]	$ (12,230)	[1]	$ (286)	[2]	$ (21)	[2]	$ (499)	[2]	$ (28)	[2]	$ (52)	[3]		$ (4,314)	[3]

[1] $4.6 million included in "Costs associated with loan refinancing" and $137 thousand included in "Interest expense" in the accompanying consolidated statements of income for the six months ended June 30, 2011. $8.7 million included in "Costs associated with loan refinancing" in the accompanying consolidated statements of income for the three and six months ended June 30, 2010. $1.7 million and $3.6 million included in "Interest expense" in the accompanying consolidated statements of income for the three and six months ended June 30, 2010, respectively.

[2] Included in "Other expense" in the accompanying consolidated statements of income.

[3] $4.3 million included in "Gain on sale of real estate" in the accompanying consolidated statements of income for the six months ended June 30, 2011. $52 thousand included in "Other expense" in the accompanying consolidated statements of income for the three and six months ended June 30, 2011.