Income Tax (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Currently Payable:
Federal	$ 518	$ (450)	$ 1,336	$ (902)
State
Deferred:
Federal	2,770	1,846	7,452	4,697
State
Total Income Tax Expense	3,288	1,396	8,788	3,795
Reconciliation of Federal Statutory to Actual Tax Expense:
Federal statutory income tax at 35%	4,372	2,409	11,327	5,160
Tax-exempt interest income	(930)	(961)	(1,861)	(1,877)
Non-deductible interest expense		210		419
Stock compensation	26	13	42	37
Earnings on life insurance	(231)	(200)	(714)	(402)
Tax credits	(18)	(13)	(36)	(26)
Other	69	(62)	30	484
Total Income Tax Expense	$ 3,288	$ 1,396	$ 8,788	$ 3,795