Securities (Securities In Unrealized Loss Position) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Investment [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	$ 49,695	$ 40,632
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(320)	(165)
Available-for-Sale Securities, Continuous Unrealized Loss Position,12 Months Or Longer, Fair Value	1,473
Available-for-Sale Securities, Continuous Unrealized Loss Position,12 Months or Longer, Unrealized Losses	(15)	0
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Fair Value	51,168	40,632
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Unrealized Losses	(335)	(165)
Residential Mortgage Backed Securities [Member]
Investment [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value		154
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses		(2)
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Fair Value		154
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Unrealized Losses		(2)
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	13,652	80,500
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(79)	(85)
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Fair Value	13,652	80,500
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Unrealized Losses	(79)	(85)
Collateralized Mortgage Obligations [Member]
Investment [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	32,222	36,126
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(117)	(140)
Available-for-Sale Securities, Continuous Unrealized Loss Position,12 Months Or Longer, Fair Value	1,473
Available-for-Sale Securities, Continuous Unrealized Loss Position,12 Months or Longer, Unrealized Losses	(15)
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Fair Value	33,695	36,126
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Unrealized Losses	(132)	(140)
State And Municipal [Member]
Investment [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	17,473	4,352
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(203)	(23)
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Fair Value	17,473	4,352
Available-for-Sale Securities, Continuous Unrealized Loss Position, Total Unrealized Losses	$ (203)	$ (23)