Investment Securities (Amortized Cost And Fair Value Of Investment Securities By Contractual Maturity) (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Schedule of Available-for-sale Securities [Line Items]
Available for Sale, Amortized Cost, Due within one year	$ 5,625
Available for Sale, Amortized Cost, Due after one year through five years	19,373
Available for Sale, Amortized Cost, Due after five years through ten years	31,265
Available for Sale, Amortized Cost, Due after ten years	86,976
Available for Sale, Amortized Cost	183,967	$ 183,861
Available for Sale, Fair Value, Due within one year	5,661
Available for Sale, Fair Value, Due after one year through five years	19,793
Available for Sale, Fair Value, Due after five years through ten years	31,999
Available for Sale, Fair Value, Due after ten years	88,166
Available for sale, Fair Value	186,260	184,373
Held to Maturity, Amortized Cost, Due within one year	240
Held to Maturity, Amortized Cost, Due after one year through five years	1,008
Held to Maturity, Amortized Cost, Due after five years through ten years	866
Held to Maturity, Amortized Cost, Due after ten years	328
Held to Maturity, Amortized Cost	2,570	2,607
Held to Maturity, Fair Value, Due within one year	270
Held to Maturity, Fair Value, Due after one year through five years	1,140
Held to Maturity, Fair Value, Due after five years through ten years	983
Held to Maturity, Fair Value, Due after ten years	369
Held to Maturity, Fair Value	2,897	$ 2,896
CMO
Schedule of Available-for-sale Securities [Line Items]
Available for Sale, Amortized Cost	13,629
Available for sale, Fair Value	13,541
Held to Maturity, Amortized Cost	0
Held to Maturity, Fair Value	0
ABS
Schedule of Available-for-sale Securities [Line Items]
Available for Sale, Amortized Cost	1,289
Available for sale, Fair Value	1,589
Held to Maturity, Amortized Cost	0
Held to Maturity, Fair Value	0
SBA certificates
Schedule of Available-for-sale Securities [Line Items]
Available for Sale, Amortized Cost	1,277
Available for sale, Fair Value	1,318
Held to Maturity, Amortized Cost	0
Held to Maturity, Fair Value	0
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Available for Sale, Amortized Cost	24,533
Available for sale, Fair Value	24,193
Held to Maturity, Amortized Cost	128
Held to Maturity, Fair Value	$ 135

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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