Stockholders' Equity of the Company - Schedule of Common Stock Issued and Proceeds Received Dividend Reinvestments (Details) - Dividend Reinvestment and Stock Purchase Plan (DRIP) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Stockholders' Equity
Issuance of common stock (in shares)	674	1,036
Dividend reinvestments/stock purchases under the DRSPP	$ 64	$ 111