Acquisition and Divestiture - Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Service fee income	$ 63,246	$ 55,161
Income (loss) from continuing operations	(9,331)	3,903
Net income (loss)	$ (8,450)	$ 5,869
Basic and diluted earnings per share:
Net income (loss) from continuing operations	$ (0.10)	$ 0.04
Net income (loss)	$ (0.09)	$ 0.06