Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value Disclosures [Abstract]

Summary of balance sheet fair values

All financial instruments of the Company are reflected in the accompanying Consolidated Balance Sheets at amounts which, in management's estimation, reasonably approximate their fair values, except for the following:

	September 30, 2016			December 31, 2015
(in thousands)	Carrying Amount		Fair Value	Carrying Amount		Fair Value
Financial assets:
Notes receivable	$	10,480	10,460	$	10,480	10,620
Financial liabilities:
Notes payable	$	1,364,200	1,478,100	$	1,699,771	1,793,200
Unsecured credit facilities	$	263,421	264,800	$	164,514	165,300

Fair Value, Interest rate ranges [Table Text Block]

The following interest rate ranges were used by the Company to estimate the fair value of its financial instruments:

	September 30, 2016		December 31, 2015
	Low	High	Low	High
Notes receivable	6.8%	6.8%	6.3%	6.3%
Notes payable	2.7%	3.8%	2.8%	4.2%
Unsecured credit facilities	1.5%	1.5%	1.1%	1.1%

Summary of assets measured on recurring basis

The following tables present the placement in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis:

	Fair Value Measurements as of September 30, 2016
(in thousands)				Quoted Prices in Active Markets for Identical Assets	Significant Other Observable Inputs		Significant Unobservable Inputs
Assets:	Balance			(Level 1)	(Level 2)		(Level 3)
Trading securities held in trust	$	29,280		29,280	—		—
Available-for-sale securities	8,017			—	8,017		—
Interest rate derivatives	476			—	476		—
Total	$	37,773		29,280	8,493		—
Liabilities:
Interest rate derivatives	$	(1,637	)	—	(1,637	)	—

	Fair Value Measurements as of December 31, 2015
(in thousands)				Quoted Prices in Active Markets for Identical Assets	Significant Other Observable Inputs		Significant Unobservable Inputs
Assets:	Balance			(Level 1)	(Level 2)		(Level 3)
Trading securities held in trust	$	29,093		29,093	—		—
Available-for-sale securities	7,922			—	7,922		—
Total	$	37,015		29,093	7,922		—
Liabilities:
Interest rate derivatives	$	(20,539	)	—	(20,539	)	—