Branch Acquisitions (Schedule Of Assets Purchased And Liabilities Assumed) (Details) (First Niagara Bank [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
First Niagara Bank [Member]
Significant Acquisitions and Disposals [Line Items]
Cash	$ 195,778
Loans	75,635
Bank premises and equipment	1,938
Goodwill	11,167
Core deposit intangible asset	2,042
Other assets	601
Total assets acquired	287,161
Deposits assumed	286,819
Other liabilities	342
Total liabilities assumed	$ 287,161

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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The amount of acquisition cost of a business combination allocated to prepaid expenses and other current assets. Does not include amounts allocated to cash and cash equivalents, marketable securities, receivables, inventory, and assets not to be used.

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The amount of acquisition cost of a business combination allocated to receivables.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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Amount of acquisition cost of a business combination allocated to other liabilities not separately disclosed in the balance sheet.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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