Schedule III - REAL ESTATE AND ACCUMLATED DEPRECIATION (Reconciliation of Real Estate and Accumulated Depreciation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Real Estate
Balance at beginning of year	$ 4,774,632	$ 4,116,556	$ 3,024,833
Change in land	(712,400)	(271,365)	(178,257)
Additions	(35,734)
Impairments	830,896	834,346	973,833
Dispositions and write-offs and land costs of sales	122,446	95,095	296,147
Balance at end of year	4,979,840	4,774,632	4,116,556
Reconciliation of Accumulated Depreciation
Balance at beginning of year	232,969	157,182	111,728
Depreciation expense	81,878	82,275	50,683
Dispositions and write-offs	(69,033)	(6,488)	(5,229)
Balance at end of year	$ 245,814	$ 232,969	$ 157,182
Building and Improvements | Minimum
REAL ESTATE AND ACCUMULATED DEPRECIATION
Estimated useful lives of assets	10 years
Building and Improvements | Maximum
REAL ESTATE AND ACCUMULATED DEPRECIATION
Estimated useful lives of assets	45 years
Equipment Tenant Improvements and Fixtures | Minimum
REAL ESTATE AND ACCUMULATED DEPRECIATION
Estimated useful lives of assets	5 years
Equipment Tenant Improvements and Fixtures | Maximum
REAL ESTATE AND ACCUMULATED DEPRECIATION
Estimated useful lives of assets	10 years
Computer, Hardware and Software and Vehicles | Minimum
REAL ESTATE AND ACCUMULATED DEPRECIATION
Estimated useful lives of assets	3 years
Computer, Hardware and Software and Vehicles | Maximum
REAL ESTATE AND ACCUMULATED DEPRECIATION
Estimated useful lives of assets	5 years