Equity and Capital (Tables)

6 Months Ended

Jun. 30, 2013

Schedule of Market Equity Distributions [Table Text Block]

During the three and six months ended June 30, 2013, the following shares were issued under the ATM equity program (in thousands, except share data):



		Three months ended June 30, 2013		Six months ended June 30, 2013
Shares issued		873		1,869
Weighted average price per share	$	54.22	$	53.37
Total proceeds	$	47,377	$	99,774
Commissions	$	709	$	1,496

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

The following table presents changes in the balances of each component of accumulated other comprehensive loss for the six months ended June 30, 2013 (in thousands):



		Loss on Settlement of Derivative Instruments		Fair Value of Derivative Instruments	Accumulated Other Comprehensive Income (Loss)
Beginning balance at December 31, 2012	$	(61,991	)	4,276	(57,715	)
Net gain on cash flow derivative instruments		—		21,664	21,664
Amounts reclassified from other comprehensive income		4,724		8	4,732
Current period other comprehensive income, net		4,724		21,672	26,396
Ending balance at June 30, 2013	$	(57,267	)	25,948	(31,319	)

Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]

The following represents amounts reclassified out of accumulated other comprehensive loss into earnings during the three and six months ended June 30, 2013 and 2012, respectively:



Details about Accumulated Other Comprehensive Loss Components		Amount Reclassified from Accumulated Other Comprehensive Loss									Affected Line Item in the Statement of Operations
		Three months ended June 30,					Six months ended June 30,
		2013		2012			2013		2012
Gains / (Losses) on cash flow hedges
Interest rate derivative contracts	$	(2,366	)	(2,366	)	$	(4,732	)	(4,729	)	Interest expense