Disclosure of Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2017

Debt Instrument, Fair Value Disclosure [Abstract]

Fair Value, by Balance Sheet Grouping [Table Text Block]

The following summarizes the fair value of the Company's mortgage loans and unsecured notes as of December 31, 2016 and September 30, 2017 (in thousands):

	Mortgage Loans				Unsecured Notes
	Carrying Value		Fair Value		Carrying Value		Fair Value
As of December 31, 2016	$	276,650	$	286,684	$	2,280,286	$	2,340,762
As of September 30, 2017	$	269,380	$	281,671	$	2,282,828	$	2,379,014