Allowance For Loan Losses, Allowance For Losses On Lending-Related Commitments And Impaired Loans (Summary Of Loans Restructured And Subsequently Defaulted Under The Restructured Terms) (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012 Loan		Sep. 30, 2011 Loan
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	121	[1],[2]	91	[1],[2]
Restructured loans	$ 114,404	[1],[2]	$ 73,838	[1],[2]
Residential Real Estate And Other [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	16	[1],[2]	10	[1],[2]
Restructured loans	3,977	[1],[2]	3,894	[1],[2]
Commercial And Industrial [Member] | Commercial Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	21	[1],[2]	32	[1],[2]
Restructured loans	15,161	[1],[2]	11,941	[1],[2]
Residential Construction [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	4	[1],[2]	0	[1],[2]
Restructured loans	3,252	[1],[2]	0	[1],[2]
Commercial Real Estate Construction Financing Receivable [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	7	[1],[2]	4	[1],[2]
Restructured loans	3,360	[1],[2]	9,779	[1],[2]
Land [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	21	[1],[2]	4	[1],[2]
Restructured loans	37,860	[1],[2]	4,507	[1],[2]
Office [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	2	[1],[2]	9	[1],[2]
Restructured loans	4,795	[1],[2]	8,906	[1],[2]
Industrial Property [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	2	[1],[2]	3	[1],[2]
Restructured loans	1,313	[1],[2]	4,020	[1],[2]
Retail Site [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	15	[1],[2]	6	[1],[2]
Restructured loans	28,097	[1],[2]	4,302	[1],[2]
Multi Family [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	6	[1],[2]	1	[1],[2]
Restructured loans	4,247	[1],[2]	548	[1],[2]
Mixed Use And Other [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Troubled Debt Restructuring Modifications Number Of Count	27	[1],[2]	22	[1],[2]
Restructured loans	12,342	[1],[2]	25,941	[1],[2]
Payment In Default [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	24	[1],[3]	21	[1],[3]
Balance	13,451	[1],[3]	15,369	[1],[3]
Payment In Default [Member] | Residential Real Estate And Other [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	6	[1],[3]	3	[1],[3]
Balance	2,379	[1],[3]	769	[1],[3]
Payment In Default [Member] | Commercial And Industrial [Member] | Commercial Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	3	[1],[3]	5	[1],[3]
Balance	351	[1],[3]	1,946	[1],[3]
Payment In Default [Member] | Residential Construction [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	0	[1],[3]	0	[1],[3]
Balance	0	[1],[3]	0	[1],[3]
Payment In Default [Member] | Commercial Real Estate Construction Financing Receivable [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	5	[1],[3]	1	[1],[3]
Balance	2,740	[1],[3]	377	[1],[3]
Payment In Default [Member] | Land [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	2	[1],[3]	3	[1],[3]
Balance	1,925	[1],[3]	4,227	[1],[3]
Payment In Default [Member] | Office [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	0	[1],[3]	3	[1],[3]
Balance	0	[1],[3]	3,899	[1],[3]
Payment In Default [Member] | Industrial Property [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	1	[1],[3]	1	[1],[3]
Balance	990	[1],[3]	1,840	[1],[3]
Payment In Default [Member] | Retail Site [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	1	[1],[3]	1	[1],[3]
Balance	1,605	[1],[3]	459	[1],[3]
Payment In Default [Member] | Multi Family [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	1	[1],[3]	0	[1],[3]
Balance	264	[1],[3]	0	[1],[3]
Payment In Default [Member] | Mixed Use And Other [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	5	[1],[3]	4	[1],[3]
Balance	3,197	[1],[3]	1,852	[1],[3]
Payment In Default [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	18	[1],[3]	19	[1],[3]
Balance	7,841	[1],[3]	14,543	[1],[3]
Payment In Default [Member] | Residential Real Estate And Other [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	5	[1],[3]	3	[1],[3]
Balance	1,931	[1],[3]	769	[1],[3]
Payment In Default [Member] | Commercial And Industrial [Member] | Commercial Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	3	[1],[3]	3	[1],[3]
Balance	351	[1],[3]	1,120	[1],[3]
Payment In Default [Member] | Residential Construction [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	0	[1],[3]	0	[1],[3]
Balance	0	[1],[3]	0	[1],[3]
Payment In Default [Member] | Commercial Real Estate Construction Financing Receivable [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	5	[1],[3]	1	[1],[3]
Balance	2,740	[1],[3]	377	[1],[3]
Payment In Default [Member] | Land [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	1	[1],[3]	3	[1],[3]
Balance	651	[1],[3]	4,227	[1],[3]
Payment In Default [Member] | Office [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	0	[1],[3]	3	[1],[3]
Balance	0	[1],[3]	3,899	[1],[3]
Payment In Default [Member] | Industrial Property [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	1	[1],[3]	1	[1],[3]
Balance	990	[1],[3]	1,840	[1],[3]
Payment In Default [Member] | Retail Site [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	0	[1],[3]	1	[1],[3]
Balance	0	[1],[3]	459	[1],[3]
Payment In Default [Member] | Multi Family [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	1	[1],[3]	0	[1],[3]
Balance	264	[1],[3]	0	[1],[3]
Payment In Default [Member] | Mixed Use And Other [Member] | Commercial Real Estate Portfolio Segment [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Count	2	[1],[3]	4	[1],[3]
Balance	$ 914	[1],[3]	$ 1,852	[1],[3]

[1] Balances represent the recorded investment in the loan at the time of the restructuring.

[2] Total restructured loans represent all loans restructured during the previous twelve months from the date indicated.

[3] Restructured loans considered to be in payment default are over 30 days past-due subsequent to the restructuring.