Accumulated Other Comprehensive Loss (Summary Of Reclassifications Out Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Provision for income taxes	$ (34)	$ 17	$ (4)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension And Postretirement Plan Adjustments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Service Cost	60	51	62
Interest Cost	1,608	1,586	1,550
Expected return on plan assets	(1,493)	(1,584)	(1,508)
Amortization of net loss	547	416	183
Total before tax	722	469	287
(Benefit) provision for income taxes	(270)	(174)	(37)
Total net of tax	992	643	324
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Realized gains on available-for-sale investments into earnings	(437)	(99)	(150)
Total before tax	(437)	(99)	(150)
Provision for income taxes	(66)	(15)	(23)
Total net of tax	$ (371)	$ (84)	$ (127)