Merger With Tier REIT, Inc. - (Pro Forma Information) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Business Combinations [Abstract]
Revenues	$ 188,323	$ 555,324
Net income	21,740	110,188
Net income available to common stockholders	$ 21,410	$ 108,724