Consolidated Statement Of Operations Consolidated Statement of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Consolidated Statement of Operations (Parenthetical) [Abstract]
Management fee rebate	$ 160	$ 172	$ 0	$ 0	$ 332	[1]	$ 0	[1]	$ 0	[1]

[1] See Note 9 for further details on management fee rebates.