SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Aggregate cost for federal Income tax purposes	$ 2,490,000
Accumulated tax depreciation	94,400
Aggregate cost for federal income tax purposes, net of accumulated tax depreciation	2,390,000
SEC Schedule III, Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance as of the beginning of the year	1,424,894	$ 729,034
Acquisitions	1,170,593	695,693	$ 505,379
Additions	11,049	4,440	900
Impairment	0	0	(1,750)
Dispositions	0	(4,273)	(225)
Balance as of the end of the year	2,606,536	1,424,894	729,034
SEC Schedule III, Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance as of the beginning of the year	61,242	32,772
Depreciation	57,367	29,958	12,473
Dispositions	0	(1,488)	0
Balance as of the end of the year	$ 118,609	$ 61,242	$ 32,772