Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interest	$ 16,320	$ 4,670
Other comprehensive (loss) income:
Change in net unrealized gain (loss) on debt securities	6,171	(7,480)
(Gains) losses realized in net income	22	1,010
Total	6,193	(6,470)
Unrealized gains (loss) on currency translation	1,433	(3,086)
Deferred income tax effect	(360)	0
Total other comprehensive (loss) income	4,400	(3,384)
Total comprehensive income	20,720	1,286
Total comprehensive income attributable to noncontrolling interest	922	0
Comprehensive income attributable to parent	$ 19,798	$ 1,286