Loans and Other Repossessed Assets Acquired (Detail) - Other Repossessed Assets Acquired (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Other repossessed assets acquired	$ 16,310	$ 18,338
Land [Member]
Other repossessed assets acquired	5,422	6,350
Residential Real Estate Assets [Member]
Other repossessed assets acquired	4,146	4,660
Commercial Real Estate [Member]
Other repossessed assets acquired	5,165	5,588
Consumer Related Assets [Member[
Other repossessed assets acquired	$ 1,577	$ 1,740