Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 22,511	$ 24,383
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on AFS securities arising during the period, net of taxes of $145 and $(1,133)	(452)	3,527
Changes in unrealized gains (losses) on cash flow hedges, net of taxes of $(1,741) and $3,128	5,424	(9,744)
Comprehensive income	$ 27,483	$ 18,166