Fair Value Measurements (Narratives) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($) property	Jun. 30, 2015 USD ($) property	Jun. 30, 2016 USD ($) property	Jun. 30, 2015 USD ($)
Fair value inputs
Goodwill, impairment loss			$ 10,191
Fair Value, Measurements, Nonrecurring | Level 3
Fair value inputs
Impairment charges on properties	$ 35,429	$ 591	35,429	$ 3,274
Goodwill, impairment loss	$ 10,200		$ 10,200
Number of real estate properties | property	14		14
Fair Value, Measurements, Nonrecurring | Level 3 | Real Estate
Fair value inputs
Impairment charges on properties	$ 35,429	591	$ 35,429	$ 3,274
Fair Value, Measurements, Nonrecurring | Level 3 | Real Estate | Properties sold
Fair value inputs
Impairment charges on properties		$ 2,700
Number of properties sold | property		2