Securities (Summaries Of Fair Values And Unrealized Losses Of Securities, Segregated By Length Of Impairment) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012 Security	Dec. 31, 2011 Security
Schedule Of Securities [Line Items]
Number of available for sale securities	27	21
Securities Available For Sale, Less than 12 Months, Fair Value	$ 101,404	$ 130
Securities Available For Sale, Less than 12 Months, Unrealized Losses	(1,275)	(10)
Securities Available For Sale, Greater than 12 Months, Fair Value	11,431	11,854
Securities Available For Sale, Greater than 12 Months, Unrealized Losses	(13,339)	(14,906)
Securities Available For Sale, Fair Value, Total	112,835	11,984
Securities Available For Sale, Unrealized Losses, Total	(14,614)	(14,916)
Number of held to maturity securities	3	6
Securities Held To Maturity, Less than 12 Months, Fair Value	16,325	18,285
Securities Held To Maturity, Less than 12 Months, Unrealized Losses	(100)	(75)
Securities Held To Maturity, Greater than 12 Months, Fair Value	477	6,773
Securities Held To Maturity, Greater than 12 Months, Unrealized Losses	(35)	(1,804)
Securities Held To Maturity, Fair Value, Total	16,802	25,058
Securities Held To Maturity, Unrealized Losses, Total	(135)	(1,879)
Less than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	14	3
Number of held to maturity securities	2	3
Greater than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	13	18
Number of held to maturity securities	1	3
U.S. Government-Sponsored Entities [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	3
Securities Available For Sale, Less than 12 Months, Fair Value	44,868
Securities Available For Sale, Less than 12 Months, Unrealized Losses	(129)
Securities Available For Sale, Greater than 12 Months, Fair Value
Securities Available For Sale, Greater than 12 Months, Unrealized Losses
Securities Available For Sale, Fair Value, Total	44,868
Securities Available For Sale, Unrealized Losses, Total	(129)
Number of held to maturity securities	1
Securities Held To Maturity, Less than 12 Months, Fair Value	14,901
Securities Held To Maturity, Less than 12 Months, Unrealized Losses	(99)
Securities Held To Maturity, Greater than 12 Months, Fair Value
Securities Held To Maturity, Greater than 12 Months, Unrealized Losses
Securities Held To Maturity, Fair Value, Total	14,901
Securities Held To Maturity, Unrealized Losses, Total	(99)
U.S. Government-Sponsored Entities [Member] \| Less than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	3
Number of held to maturity securities	1
Agency Collateralized Mortgage Obligations [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	3
Securities Available For Sale, Less than 12 Months, Fair Value	47,174
Securities Available For Sale, Less than 12 Months, Unrealized Losses	(228)
Securities Available For Sale, Greater than 12 Months, Fair Value
Securities Available For Sale, Greater than 12 Months, Unrealized Losses
Securities Available For Sale, Fair Value, Total	47,174
Securities Available For Sale, Unrealized Losses, Total	(228)
Number of held to maturity securities		1
Securities Held To Maturity, Less than 12 Months, Fair Value		12,911
Securities Held To Maturity, Less than 12 Months, Unrealized Losses		(11)
Securities Held To Maturity, Greater than 12 Months, Fair Value
Securities Held To Maturity, Greater than 12 Months, Unrealized Losses
Securities Held To Maturity, Fair Value, Total		12,911
Securities Held To Maturity, Unrealized Losses, Total		(11)
Agency Collateralized Mortgage Obligations [Member] \| Less than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	3
Number of held to maturity securities		1
Collateralized Debt Obligations [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	16	12
Securities Available For Sale, Less than 12 Months, Fair Value	8,708
Securities Available For Sale, Less than 12 Months, Unrealized Losses	(909)
Securities Available For Sale, Greater than 12 Months, Fair Value	5,532	5,998
Securities Available For Sale, Greater than 12 Months, Unrealized Losses	(12,367)	(13,226)
Securities Available For Sale, Fair Value, Total	14,240	5,998
Securities Available For Sale, Unrealized Losses, Total	(13,276)	(13,226)
Number of held to maturity securities	1	1
Securities Held To Maturity, Less than 12 Months, Fair Value
Securities Held To Maturity, Less than 12 Months, Unrealized Losses
Securities Held To Maturity, Greater than 12 Months, Fair Value	477	1,278
Securities Held To Maturity, Greater than 12 Months, Unrealized Losses	(35)	(314)
Securities Held To Maturity, Fair Value, Total	477	1,278
Securities Held To Maturity, Unrealized Losses, Total	(35)	(314)
Collateralized Debt Obligations [Member] \| Less than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	7
Collateralized Debt Obligations [Member] \| Greater than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	9	12
Number of held to maturity securities	1	1
Other Debt Securities [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	4	4
Securities Available For Sale, Less than 12 Months, Fair Value
Securities Available For Sale, Less than 12 Months, Unrealized Losses
Securities Available For Sale, Greater than 12 Months, Fair Value	5,899	5,197
Securities Available For Sale, Greater than 12 Months, Unrealized Losses	(972)	(1,666)
Securities Available For Sale, Fair Value, Total	5,899	5,197
Securities Available For Sale, Unrealized Losses, Total	(972)	(1,666)
Number of held to maturity securities		1
Securities Held To Maturity, Less than 12 Months, Fair Value
Securities Held To Maturity, Less than 12 Months, Unrealized Losses
Securities Held To Maturity, Greater than 12 Months, Fair Value		1,144
Securities Held To Maturity, Greater than 12 Months, Unrealized Losses		(181)
Securities Held To Maturity, Fair Value, Total		1,144
Securities Held To Maturity, Unrealized Losses, Total		(181)
Other Debt Securities [Member] \| Greater than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	4	4
Number of held to maturity securities		1
Equity securities [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	1	4
Securities Available For Sale, Less than 12 Months, Fair Value	654	100
Securities Available For Sale, Less than 12 Months, Unrealized Losses	(9)	(9)
Securities Available For Sale, Greater than 12 Months, Fair Value		659
Securities Available For Sale, Greater than 12 Months, Unrealized Losses		(14)
Securities Available For Sale, Fair Value, Total	654	759
Securities Available For Sale, Unrealized Losses, Total	(9)	(23)
Equity securities [Member] \| Less than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities	1	2
Equity securities [Member] \| Greater than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities		2
Non-Agency Collateralized Mortgage Obligations [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities		1
Securities Available For Sale, Less than 12 Months, Fair Value		30
Securities Available For Sale, Less than 12 Months, Unrealized Losses		(1)
Securities Available For Sale, Greater than 12 Months, Fair Value
Securities Available For Sale, Greater than 12 Months, Unrealized Losses
Securities Available For Sale, Fair Value, Total		30
Securities Available For Sale, Unrealized Losses, Total		(1)
Number of held to maturity securities		3
Securities Held To Maturity, Less than 12 Months, Fair Value		5,374
Securities Held To Maturity, Less than 12 Months, Unrealized Losses		(64)
Securities Held To Maturity, Greater than 12 Months, Fair Value		4,351
Securities Held To Maturity, Greater than 12 Months, Unrealized Losses		(1,309)
Securities Held To Maturity, Fair Value, Total		9,725
Securities Held To Maturity, Unrealized Losses, Total		(1,373)
Non-Agency Collateralized Mortgage Obligations [Member] \| Less than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of available for sale securities		1
Number of held to maturity securities		2
Non-Agency Collateralized Mortgage Obligations [Member] \| Greater than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of held to maturity securities		1
Agency Mortgage-Backed Securities [Member]
Schedule Of Securities [Line Items]
Number of held to maturity securities	1
Securities Held To Maturity, Less than 12 Months, Fair Value	1,424
Securities Held To Maturity, Less than 12 Months, Unrealized Losses	(1)
Securities Held To Maturity, Greater than 12 Months, Fair Value
Securities Held To Maturity, Greater than 12 Months, Unrealized Losses
Securities Held To Maturity, Fair Value, Total	1,424
Securities Held To Maturity, Unrealized Losses, Total	$ (1)
Agency Mortgage-Backed Securities [Member] \| Less than 12 Months [Member]
Schedule Of Securities [Line Items]
Number of held to maturity securities	1

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Amount of the excess of amortized cost basis over fair value of securities that have been in a loss position for twelve months or longer for securities which are categorized neither as held-to-maturity nor trading securities.

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Amount of the excess of amortized cost basis over fair value of securities in a loss position and categorized neither as held-to-maturity nor trading securities.

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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