Mortgage Notes Payable Schedule of Aggregate Principal Payments On Mortgage Notes (Tables)

12 Months Ended

Dec. 31, 2012

Mortgage Notes Payable [Abstract]

Schedule of Aggregate Principal Payments On Mortgage Notes [Table Text Block]

Contractual aggregate principal payments of mortgage notes payable at December 31, 2012 are as follows: 

	Principal Payments
	(in thousands)
2013	$	105,313
2014	87,757
2015	26,182
2016	608,879
2017	1,521,750
Thereafter	713,960
Total aggregate principal payments	3,063,841
Unamortized balance of historical fair value adjustments	38,644
Total carrying value of mortgage notes payable	$	3,102,485