Accumulated Other Comprehensive Income - Activity in Accumulated Other Comprehensive Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Schedule of Available-for-sale Securities [Line Items]
Beginning balance, Accumulated Other Comprehensive Income/(Loss)	$ (1,846)	$ 163	$ (1,235)	$ 1,758
Other comprehensive income (loss) before reclassifications	2,165	(4,194)	1,701	(5,431)
Amounts reclassified from accumulated other comprehensive income	12	58	(135)	(300)
Period change	2,177	(4,136)	1,566	(5,731)
Ending balance, Accumulated Other Comprehensive Income/(Loss)	331	(3,973)	331	(3,973)
Provision for income taxes	976	519	2,146	2,542
Defined Benefit Pension Plan [Member]
Schedule of Available-for-sale Securities [Line Items]
Beginning balance, Accumulated Other Comprehensive Income/(Loss)	(1,297)	(4,318)	(1,306)	(4,450)
Amounts reclassified from accumulated other comprehensive income	5	65	14	194
Period change	5	65	14	194
Ending balance, Accumulated Other Comprehensive Income/(Loss)	(1,292)	(4,253)	(1,292)	(4,253)
Unrealized Gains (Losses) on Securities Available for Sale [Member]
Schedule of Available-for-sale Securities [Line Items]
Beginning balance, Accumulated Other Comprehensive Income/(Loss)	(549)	4,481	71	6,208
Other comprehensive income (loss) before reclassifications	2,165	(4,194)	1,701	(5,431)
Amounts reclassified from accumulated other comprehensive income	7	(7)	(149)	(494)
Period change	2,172	(4,201)	1,552	(5,925)
Ending balance, Accumulated Other Comprehensive Income/(Loss)	1,623	280	1,623	280
Reclassification Out of Accumulated Other Comprehensive Income [Member]
Schedule of Available-for-sale Securities [Line Items]
Net of tax	12	58	(135)	(300)
Reclassification Out of Accumulated Other Comprehensive Income [Member] \| Defined Benefit Pension Plan [Member]
Schedule of Available-for-sale Securities [Line Items]
Compensation and employee benefits	7	98	21	294
Provision for income taxes	(2)	(33)	(7)	(100)
Net of tax	5	65	14	194
Reclassification Out of Accumulated Other Comprehensive Income [Member] \| Unrealized Gains (Losses) on Securities Available for Sale [Member]
Schedule of Available-for-sale Securities [Line Items]
Gain on sale of investments, net	10	(11)	(226)	(749)
Provision for income taxes	(3)	4	77	255
Net of tax	$ 7	$ (7)	$ (149)	$ (494)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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