Business Combinations (Pro Forma) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Business Acquisition, Pro Forma Information
Operating revenue	$ 124,626	$ 87,387	$ 232,856	$ 166,490
Net Income (Loss) Attributable to Parent	$ 29,180	$ 23,434	$ 55,388	$ 49,861
Basic EPS	$ 0.93	$ 0.74	$ 1.76	$ 1.58
Diluted EPS	$ 0.92	$ 0.74	$ 1.75	$ 1.57
Revenue, Net, Increase (Decrease)	$ 37,239		$ 66,366
Revenue, Net, Increase (Decrease), Percentage	39.90%		42.60%
Operating revenue	$ 124,626	$ 87,387	$ 232,856	$ 166,490
Parent, ItzCAsh, beBetter, YouFirst, WallStreet, PML, Via, and Transcorp [Member]
Business Acquisition, Pro Forma Information
Revenue, pro forma	124,626	123,996	248,614	253,945
Net income, pro forma	$ 29,180	$ 26,291	$ 57,140	$ 57,535
Basic EPS, pro forma	$ 0.93	$ 0.83	$ 1.82	$ 1.82
Diluted EPS, pro forma	$ 0.92	$ 0.83	$ 1.81	$ 1.81
Business Acquisition, Pro Forma Revenue, Increase (Decrease), Percentage	0.50%		(2.10%)